Lost My Boyfriend And A Friend :(

Hi am 19 years old and I met my ex bf about 4 months ago through his friend and my friend. We totally hit it off right away and was pretty much unseperable after that. We hung out almost ever day and about a month in he asked me to be his girlfriend and of coarse I was so happy. We were so perfect for each other I felt like he was another part of me. I even stayed at his place for about 2 weeks when I had no place else to go and that made us even closer. We could tell each other things we could never tell others before. Then one day that all came crashing down. There was no signs he was going to break up with me but 2 months into our relationship he broke up with me. He said he still wanted us to be close friends like before and I knew this wasn't a good idea but I cared about him so much that I agreed. Then I find out 4 days later after he broke up with me that he already started dating one of his co-workers. I was so made at him and I wanted to lose all contact with him right then and there but something told me to hold on. He told me he still wanted to be friends despite having a new gf and I still loved him so yet I agreed. Everything was fine until about 1 week in of them dating. His gf pretty much said her or me. Of coarse he picked her and he said that he needed to remove me from his life. This was so hard to hear someone you care so much about and u cant be friends with them. But he still cont. to talk to me and I was there for him when he was having problems with his relationship. In way a got a high from hear all his problems with his new relationship which made me cont. to be there for him. After about 3 weeks of their relationship she broke up with him. Of coarse he came running back to me and I was right there waiting for him. And he totally messed with my head giving me false hope that we would probably get back together and how much he missed me and that he still loved me and even felt more of a connection now then ever before. Everything was good for a week. We hung out for a week just like old times. Unseperable. Then he texted me and was like am going back to alyssa and we cant be friends or hangout again. And its been a day since this has all happend. And as am typing this he has texted me after he said he could have be in his live again. Y does he keep doing this to me. Does he think that he can walk all over me and I will be there in a heartbeat for him, Or does he just like messing with my head. Please help me out the more I know about what really is going on with us the faster I will be able to move on!!