I'll start by saying sorry if I'm all over the place with this but just try and bear with me! So in the beginning of our relationship everything was great and we fell in love almost right away. We always saw each other and wanted to be together. I'm a very affectionate and loving Guy and I hide the fact that I'm a sensitive guy except with her. I always put her in front of everything else in my life. But after a year into our relationship I feel she doesn't and I don't expect her too but it hurts that she doesn't put into consideration how her needs and wants affect me. She has became less affectionate over the period of our relationship but I do know that she still truly loves me.
I feel with almost every argument we have I am the one who is affected more so then her because I make sure her needs are met before mine so she could be happy and we don't have to argue. When she is happy and chipper so am I because there is no arguing or fighting just us messing around and loving each other. But all the arguments we had, which is almost none but just big ones, are slowly starting to weigh me down and make me feel like I am the only one in this relationship who is making sacrifices.
When we started dating most of my friends were leaving for college so her friends became mine just from us all hanging out. But now when I'm with her and our friends she pays attention to everyone else except me the whole night. I'm not asking for her to be by me the whole night but she literally separates herself and hangs out with her friends who are mostly guys. I have grown Pretty close with them sense I've known them for over a year now. My girlfriend and I recently talked about how it bothers her that I go and hangout with them(just the guys)but they're my friends too and in the beginning she wanted them to be. Now sometimes when there is a party or they are just hanging out and they tell her to invite me she doesn't because she wants to spend time with them without me there and she tells them that I'm busy when she never even told me about it. The most recent event is one of her best friends is moving in with me and she doesn't want that at all because they are her friends. It hurts that she doesn't put into account that they are the only friends I have and I'm not the best at making them! Is she being a selfish person or am I over reacting and what should I do? Please try and limit the comments about breaking it off because that is a last resort.

I won't suggest to break up with her. It sounds like a hard situation and it may be one that could take a while to fix. What I got from this is you spoiled her. Its not that either of you are selfish. She adjusted to having her way very often since you put her first all the time. You may need to change things up and take a little more control of the situation. Its sweet that you do as much as you do for her but you do need to put yourself first from time to time. I hope I helped :) Good luck with everything!

The problem here is that you have allowed her to have too much control. It is OK to compromise... it is NOT OK to let her step all over you. In an argument you come up with a solution that is best for the both of you, not just her. Try doing this from now on, see how things get better.

I had a little trouble following who was spending time with whom and who was being left out when, but what I do understand is that it seems she's lying to you and you're unhappy. If you really love her you should make an effort to make this relationship work well for both of you. It seems that she's not acknowledging your feelings, only her own. It also seems that she likes relationship dynamics to work solely around her. This is evidenced by the fact that she often likes to hang out with your friends without you (this is odd, suspicious even). She seems to like being/needs to be the center of attention. Be careful with people like this. They have ways of making you feel like the bad guy when you're not.

Try to fix things and if she isn't willing to listen to you and you don't see any changes that you feel need to happen, then leave. Otherwise, you could spend years trying to make a person happy who isn't returning the favor.