I'm a gay trans guy, and there's this one boy, N, who misgenders me constantly. He's bi, and I know it's not intentional--he says sorry after he does it, even though I have to correct him myself. However, he misgenders me literally every time he talks in third person, and it's incredibly annoying and insulting. I want to be friends with him--he's really nice, and we both like theatre and have similar senses of humor--but I'm not sure if I should. In addition to this, he confided in one of my friends that he has a hard time seeing me as a boy. My friend told me this, but made me promise not to tell N, because N confided in him. But this makes me really mad--nobody misgenders me as much as N, he doesn't seem to get how serious it is, and never corrects himself. I really want to confront him about saying that, but I'm afraid that it would violate my friend's trust in me, and cast my friend in a bad light. Whenever N misgenders me, afterwards I always resolve to confront him about it the next time, but when he does it I get ashamed and forget until an hour or so has gone by. I just want to make him stop misgendering me so we can be friends. What should I do?
I'm so sorry that N is constantly misgendering you; that sounds like a painful situation. I know from experience that it can be incredibly hurtful and demoralizing to have someone in your social circle do this even after being corrected multiple times. Even if he acts like this behavior isn't a big deal and downplays the impact it has on you, your hurt feelings and anger are valid. This isn't the behavior of a good friend or ally .
N may not be explicitly thinking: "I want to hurt this person via constant misgendering," but he is intentionally deciding not to put forth the effort of talking about you properly.
Constant, persistent misgendering after being corrected isn't an accident; it's a choice he's making. He's decided his view of you wins out over what you have explicitly told him. You say he's really nice, but I'm not seeing much niceness here. Perhaps he's being superficially friendly to you, but he's not being kind or respectful, which I would argue are more important. It's not all right for him to base the language he uses for you on how he sees you; it's on him to follow your lead and use the language you've asked for when he's speaking to or about you. He may say he's sorry when he makes this mistake, but an apology is completely empty if it doesn't come with any concrete effort to do better.
If I sound angry here, it's because I am. It's hard to be in the position you're in. You shouldn't have to keep reminding people not to misgender you. I find that a lot of cisgender people tend to downplay or dismiss the emotional damage that constant misgendering can do, but it can cause a lot of pain and distress. In my own social transition , I found it nearly impossible to correct friends who continued to misgender me after I'd come out to them. I could find the courage to correct them maybe one or two times, but if they persisted I found myself thinking: "I guess I just haven't earned this yet." Every time someone used the wrong pronouns for me, I felt paralyzed and ashamed, and it was rare that I was assertive enough to speak up. Afterwards I'd be angry at them and at myself for my silence. If speaking up in the moment is too stressful for you, it may be a better idea to take N aside at some point when he hasn't just misgendered you and you're feeling more able to discuss this issue, and talk to him about this pattern of behavior. Or, if talking face-to-face at all feels too intimidating for now, you could write a letter to give to him to read later. In fact, writing a letter might be helpful whether or not you intend to send it to him; sometimes getting all the things you want to say to someone down on paper can help you organize your thoughts and figure out what feels most important to address.
I understand that you don't want to let N know your friend shared a private conversation with you, but you don't need to discuss his difficulties seeing you as a boy in order to let him know that he needs to stop misgendering you. You could confront N about this situation even if you hadn't heard anything from your friend, and you don't need to bring up that detail during the course of your conversation if you'd rather not. It's a piece of information that gives you additional context about N's frame of mind, but it doesn't make the language he uses for you any more of less of a problem. While of course it would be best if he accepted your gender and saw you the way you see yourself, it's his behavior that's the real problem here.
While it may be that N just isn't willing to respect your gender, it makes sense to have a very direct conversation where you're clear about what you need from him before you decide if he should have more of a place in your life or not. Ignorance is a poor excuse for misgendering, but on the off-chance he doesn't quite understand the situation and how painful this is for you, it may be worth a try to clarify things one more time and let him know that using the correct language isn't optional, but necessary. A sample script could be "I need to talk to you about how often you misgender me. I know you know the right pronouns (or name, etc.) to use for me and I've corrected you many times. You keep apologizing, but nothing's changed. No matter how you see me, it's really important to me that you make a real effort to call me by the correct name and pronouns. Can you do that moving forward?"
Even though N seems like someone you should be able to be better friends with, that perceived compatibility doesn't always mean you'll be a great match. I understand how frustrating it can be to think someone should be a great friend based on their interests or attributes that overlap with yours, but it takes more than that to form a real friendship, and shared interests don't always lead to forming an emotional bond. As long as he's disrespecting you like this, I don't think a close friendship is going to be possible, but if he's able to listen to you and change his behavior, it might be possible at some point. If he brushes you off, tries to downplay the impact of what he's doing, or says he'll do better but doesn't change anything, I think that'll be a sign that this just isn't a friendship that's meant to be. If he isn't willing to show you basic respect, he's not someone who deserves your friendship.
In addition, I think it's worth talking to the friend who told you about the conversation he had with N, and asking him not to do that in the future. I don't think much good can come from passing on negative things one person says about another. If there's a situation where a friend is supportive to your face and badmouthing you or your gender behind your back, that might be something you'd want to know about, but when a person is already unsupportive, learning further details about how they see you is likely to just make things hurt more. You may not feel the same way I do about this, but if you do, I encourage you to ask your friend to be more thoughtful about what he passes along to you.
Another thing you could discuss with this friend, and possibly with other friends as well, is whether there are supportive responses they're willing to provide if N misgenders you in the future. That might involve them actively pointing out and correcting N's missteps, or pointedly modeling correct use in response if they don't want to address his mistakes directly. (For example: if he asks "Does she like dogs?" they might respond "He likes them a lot, they're his favorite animal.") It can be easier for those who aren't the subject of misgendering language to step in and say something in the moment, and sometimes that additional social pressure can have a big impact on people who are otherwise reluctant to change their behavior.
Ultimately, I know your question is about how to stop N from misgendering you, and the frustrating truth is that you can't. You can remind someone of the correct language to use, and you can tell them how hurtful it is when they get it wrong, but the real change has to come from them. While I hope N can change his behavior and get to a point where he can be a better friend and ally to you, I want to remind you that if he doesn't do those things, that's something that reflects poorly on him, not on you. Someone not respecting your gender isn't about you not being trans in the "right" way or not performing gender correctly; it's about that person making a choice to be disrespectful and unkind.