I'm so confused! Help!

So I have been with my partner for a year. He has a child from a previous relationship that I was well aware of before "signing up". His ex also has another child from another of her previous relationships. My partner has been to court to get access to his child. I am slightly older than him and have no children.

Before going to court he was seeing the child irregularly for about 4 months but ALWAYS done at her house. One day he went round and she pounced on him and kissed him! He told me two weeks later and it broke my heart, I felt so empty.

We carried on our relationship and she stopped access. So he went to court to get access.

Except it has all now gone back to being at her place! My boyfriend says I just want to see the girls, yes he's allowed to see the child that isn't his!

They text frequently throughout the day and I'm not sure what there is to be texting that much. He hides the texts from me which really gets to me.

I have no issue with him seeing his child but why is it done at her house? I'm accused of being jealous and insecure. I just can't trust her especially after what happened before.

Why would you want your ex round your house?! And then to say you can come round and help put them to bed and we can have dinner together. Seems too much like playing happy families to me.

The whole thing upsets me, I tell my boyfriend this but just says I'm being stupid, shouts at me and storms off!

I'm so confused as what to do! I'm scared that he will go back as that's a way for him to see the kids all the time and the fact that they are probably getting on better than we are currently!

I don't want to split up with him, when we are good, we are really good. We have so much planned together.

It breaks my heart. I have no one to talk to about this and just need some advice and possibly someone to talk to!