Hi everybody, I'm not sure that this is the right group. I

Hi everybody,
I'm not sure that this is the right group. I am not a good friend! Since my first girlfriend I have dumped my friends when I got in a relationship. I got my first girlfriend when I was about 14, I ignored my friends and just spent time with her. I pretty much lost those friends. I'm 54 now and I see my old friends on fb and they still get together but no one calls me. They say happy birthday because that's what everybody does but I don't get invited to get togethers. When I was bout 19 I was in a band, we traveled and played in bars and hung out. Five of us. I was the youngest and wasn't completely comfortable with some of the things they were doing, they were in their mid 20's but seemed so much older. I didn't really feel like I fit in. I got a girlfriend and she got pregnant. I quit the band to get a real job and be responsible. I lost that group of friends, I didn't call, or stay in touch. I lost them too. Yesterday I saw one of them on fb and sent him a friend request. He has created a band page from the old days and there I am 30 years ago and next to that picture is a picture of the other four guys from last year, standing with their arms around each other. They're still friends 30 years later. I could have been part of that group of friends.
I have one friend from my time in university, approximately 20 years. We would do anything for each other, we are like brothers but not because of me. Sure I have been there for him in his darkest times and he for me but that isn't because of me. That's because of him. I don't call, I don't reach out, I make no attempt to stay in contact. He did that! I do call and stay in touch with him but we are the end of friends that don't have to talk regularly. I am a great friend to him but he is the only one. I think that I have been a ****** friend to a lot of people, I just didn't put in the effort. The woman I was with was always the centre of my universe and when those relationships end there I am all alone so I quickly get into another one.
I hope that I haven't hurt people, I don't know why I am this way.
When I was very young we moved a lot. I think 7 times by the time I was 7 or 8 and we didn't just move down the street, we moved to different states and countries. The only constant relationship that I had during that time was with my older sister. She was older than me, she looked after and protected me and she was my friend. I wonder if I try to recreate that in my relationships and try to hold on to that too much and make it the centre of my world so I don't lose it, because i didn't learned how to develop long lasting relationships outside of my immediate family. I don't know. I am sorry for the length of my message. I don't like being this way and I want to have friends!
Thanks for reading this.