Hey, girlplayer34, hope it's okay that I'm jumping in! Just wanted to say that it seems to me that the issue isn't with you or your height, but with the people around you. The only thing that seems different to me about Sam's tall friends and you is that they are around different people who aren't as rude or insecure when it comes to height!
There's also a huge problem with the culture we have around media sources telling us what girls need to look like - so many of the expectations are unreasonable and tell girls that they need to change things that are literally unchangeable (especially in straight culture, where for some reason men's pride is all tied up in how they need to be bigger than a woman. Hello, fragile masculinity!). That's simply not your fault - you're just existing in your body. I'm hearing that you want to find people excited to date a tall girl - what makes you feel excited about being in your body? Is there anything that you really like about being tall?
I know it feels really important to get someone to date you right now, but it could help to try and trust that that person is simply not around right now. You're gonna go so many places and meet so many people - you never know when you'll meet that person who LOVES tall girls. And people do, trust me - just google "I love tall girls"!
Also - I haven't seen the show myself, but there is a show called "Tall Girl" on Netflix which deals with the insecurity that someone has being taller than everyone else - I wonder if you've seen it, or if you could relate to that plotline?