I'm so lost..

So basically, I'm 17 and really lost right now in my life. I know what school I want to go to, what my major will be, what grad school I want, I have an amazing boyfriend who supports me, I have everything I physically need (albeit my home life can be a little stressful with my parents), and my grades are nice. But.. for some reason I'm just not.. Okay? I'm going to a therapist ( I just couldn't handle the intensity of feelings anymore) and she said I have some anxiety. I was shocked by this because well.. I thought I was just depressed, not anxious. I just... I feel so so alone and I've felt like this for a very long time and I hate it. I hate myself for being like this. I just want friends but no matter how hard I try I end up in my room, isolated, holding everything in because I hate crying or being angry.. or anything negative. I just.. Hate this. How do people make friends and keep them. I need to know. Whenever I do make a semi friend I always get too excited and chase them away making myself looking like an even bigger dumbass than before, but I just can't stop. I can't stop seeking attention when everyone else seems to be able to. What the hell is wrong with me? Am I so unstable that I can't even sustain my own existence? Sorry for the long post.. I'm not expecting anyone to read or respond. I just needed to say this. Somewhere.