Why do women give up so much for their Narcissist?

My ex has a history of relationships where woman give up everything to be with him, myself included. Women in his past left their children, left husbands, moved across many states to be with him, and almost every single one of them has been left by him for someone else.

I left my family and friends to be with him. Once married, I gave up my profession to move from state to state to support his professional growth. With each move, I became more resentful. We moved every couple of years for his job. Not because he needed a new job, but because he wanted a new job. I never felt like I could put down roots, or pursue my goals because we were always pursuing his.

If I wasn't supportive, and didn't go along with the plan, then I was being unappreciative, and selfish. He made way more money than I did, so that was always the final line. Yes, we lived in beautiful homes, so therefore I had no right to be unhappy. Honestly, I didn't care about the beautiful homes. I just wanted to feel like a partner. I wanted to be a part of these decisions. I wanted my contribution to us to matter.

It didn't matter. Once I showed any signs of discontent or resentment, I was just an unappreciative wife. He once even told me that he had no respect for me because I gave up my career. I gave up my career, because we had to keep on moving for his, and because he and I made a decision it was best for our little kids if I stayed home until they were in kindergarten.

His new girlfriend gave up her marriage, gave up full custody of her kids. My husband doesn't want her kids around full time, gave up her job,,,she got fired due to their affair.

Why do we give up so much for these men?