10 years with partner. He lived with me in my house for 4 years. He then moved out for 18 months because of family traumas (children) we were still seeing each other. Bought a house together 4 years ago no other financial commitment. Bought me a commitment ring. Now we have been together 10 years and I told him I wanted to get married which he has always know. And he has said NO point blank no that he doesn't ever want to get married again to me or anyon. He left his wife for me 10 yrs ago... Why won't he marry me and what should I do. I'm no spring chicken early 50's. He just says he loves me and wants to be with me but does not want to be married. He won't even wear a commitment ring which I would have liked to have bought him but he says he doesn't want one of them either.

Why won't he marry you? He's the only one who knows. Ask him. Presumably you share a life - and a bed - and discuss other issues in your lives. This is simply one of those issues.

He was married and wasn't faithful. Perhaps he's afraid he won't be faithful again.

Maybe he likes the situation the way it is.

You can't make anyone do anything they don't want to do.

Ask him.

You say he left his wife for you 10 years ago but you don't mention if they are divorced!
Has he in fact divorced his wife or are they still legally married?

Obviously if he is still married, then he could not marry you.If on the other hand they did divorce,maybe it cost him a lot of money,should you not work out he would not be prepared to go through losing everything again.

It could simply be that he doesn't feel the need to be married,as far as he is concerned you live as a married couple, he should not have to prove himself.

Perhaps there is still a connection there with him and his ex,you mentioned children, do you mean his children?maybe he has made some kind of commitment to them!

I think the two of you need to sit down and talk this through.