Confused

I fell in love with a man I was dating, but he wanted to marry and I was afraid to commit. He thought then that I didn’t love him. We “took a break” from dating. Three months later, we ran into each other and I said I wanted to date again. But he met someone and married on the rebound. He just wanted to be married. He says now, that he didn’t know that I really loved him. He said he will leave his wife that he only has known for 3 months. But I am not the type to “cheat” or “steal” another’s husband. I know he will do it, but I feel obligated to say “no”. I love him so much. Confused.