Fiancés spinning my mind

So I’ve been engaged for two months to a man who I’ve been engaged to for 6 months, last year. He is 30 and I’m 23. A few months ago I moved in with him and his brother. Long story short, I know he was talking to this girl as “friends” before I came back into the picture. But I told him that it made me uncomfortable if he talks to her or likes her social media things because she posts very sexual photos. I found out lastnight that last week he texted her saying “ if you need to vent I’ve got your back, you can always come talk to me, remember that.” And this bothered me a lot. Basically he KNOWS that it would upset me. I even have a doctors appointment at the end of the month to TTC with help. We’re having intimacy issues a lot which sucks because my sex drive is very high and his isn’t. I keep thinking I should just leave before it’s too late… but lastnight he sent me this long text saying he’s sorry for saying no to making love the other night and how he knows it upset me. I hate not knowing if this is just a circle. Either it’s super bad or super good with us….