Relationship Challenges

I've recently found out my boyfriend has been dealing with an issue that's affecting our relationship. It has something to do with a past relationship but I just don't understand why is it affecting him after months and moths have passed.

It's causing me to worry for our relationship due to the fact he seems down don't really show me affection as much and I feel like I'm by myself sometimes, it's stressing me out and making me angry to the point I want him to feel how I feel.

I love him and want us to be together but I just don't know what to do anymore and I'm worried for my baby. I'm 12wks and 3days. I just want us to be happy and love each other again. What should I do to help us grow and be more involved with one another. Will sex help us it's been a little while due to complications with my health but I see my doctor tomorrow to get the okay, I thought maybe we need to talk and make love again to help us realize we want each other and that we just need to work on things together than apart.