<human>: I've been in 2 'relationships'.

The first, I was in a relationship for almost a year but it wasn't like your normal relationships. I say so because even though he would call me his girlfriend we wouldn't do things that couples do. We hardly spoke to each other on the phone(he hated talking on the phone), we hardly saw each other(distance) and hardly went out.This was my very first relationship so, I was the type of girlfriend that wasn't demanding, didn't show emotion, I didn't nag and argue because I don't want to seem controlling and clingy. I had friends that were exactly like that and I didn't want to be that kind of gf. In the end, an incident happened that made us realize that we didn't love each other so the break up was easy. We had a fwb relationship for a couple of months (at the time I wanted to start over) but I realized that it wouldn't move past sex. I got out of it.

Fast forward to now, my second relationship lasted a year and a half with a great guy [35M]. He was smart, great looking, great listener,we went out alot..etc. I trusted him.This time I tried to be careful .I made sure that I was open with my feelings, I told him exactly what's on my mind. I made sure that I didn't make the same mistakes I did in my first relationship but in the end, I still got played. In November 2015 he got married 6 days after we made back up and started getting intimate again. He was hoping that I wouldn't find out about his wife. I also found out that he and his wife work at the same place which means that the both of them could have been in a relationship for a long time.
I would like some advice because right now the second incident has completely turned me off from dating because it seems like no matter what I do, I get reduced to the side piece. I don't want that. I'm a great person, I respect people, I try my best to be a great gf and I have a nice personality.

Could you distill the essence of the text into 1-3 sentences?
<bot>: I want to be in a committed, stable relationship but I always manage to be the side piece or slip into fwb relationship. What do I do?