My relationship is in a way similar. I am 20 years old now, but I've been dating my SO since I was 17. Before that I knew him for 5 years and we are best friends first and foremost. We have been basically set on engagement for a long time, and since I at least was very young (I was probably 18 at the time...wow, time flies, because it doesn't feel that long ago now) many people think that I couldn't possibly be serious. I really am, though--we are.
What I will say is that talking about becoming engaged and actually doing it are a long way apart in my mind. What I mean is, actually getting engaged means that you're planning to join two families. Once you do this, I guarantee you that the pressure you feel to remain in a relationship and/or pressure you get from family (either side) will be greater or feel greater just because now you guys have made this commitment. Friends of mine who are engaged routinely tell me how scary it is when they are upset with or fighting with a SO because it is so much more serious now that they're engaged... The same will happen, I'm sure, with familial relationships.
So I think that to an extent they are probably right. I mean, personally, I know that my SO and I will be engaged eventually. We will also marry eventually. But I know that WE know that and we don't HAVE to do those things in order to know how we feel about one another. So just the fact that we know it will happen in the future is enough. I'm willing to delay it all a lot to avoid all of those kinds of pressures from family and such because ultimately it's what me and my SO feel for one another that matters and I don't want to complicate that by giving my family or his a free ticket to nag or criticize us. Because once we've made the commitment of engagement I think it'd open the door to that stuff, especially because when you're getting married you're doing something that will, in the long-run, effect both families. They think: oh wow. Now I can be so critical about this because IT'S SERIOUS and it's MY business.
So my advice would be: YOU know what you want and so does your BF. Keep things nice and simple for as long as you can.
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