Depressed and pregnant 😭

My fiancé his ex and I have all been really good friends for a very long time. She has been hanging around his brothers house for almost a year now. So we see her about once a week. He is normally in the living room aging video games with his brother and I am sitting down with her and his (my fiancés) sister in law. But right now I am so upset at the fact that she is around. Before I was pregnant I could careless. Him and I have been together for a while now and they have been broken up for 5 years. But every time I see her I legit want to punch her. Now we have been fighting a lot and when I get mad I just tell him to go run back with her. I know it is wrong to say but I am so hurt by all of it. Then I start crying because I am thinking that he might do that. I hate feeling this way because we all got along so well before and I am not a jealous person. 😭