need advice please about SO (kind of long)

Domynique • Happily taken and a mommy to a beautiful girl

We've been together for a year. He has a child with his ex and for the past year she's caused nothing but problems. Now they are on speaking terms again and he deletes his messages with her and call log, never calls her infront of me. Last night she texted and called saying to call her back so I asked if he can do it in front of me and what he did is called her, told her I wanted him to call her and that he thinks I'm jealous of her and they began to laugh and continued to talk making plans to hang out. He asks me if I wanted to talk to her and said "she wanted me to call you but doesn't want to talk to you" Before hanging up she told him to tell me that she wears big girl pants and they both laughed and hung up.

I only wanted him to call in front of me to make sure there was nothing going on not to be made like a fool. I'm so hurt and angry. What should I do?