Pregnant and found my fiancé trying to pay someone for sex

So we have a daughter together who is 2 years old and are engaged. He has cheated on me in the past and we tried to work on it . It’s been so difficult getting over the betrayal because we’ve been together for 10years . He’s basically the only person I have had many experiences with . And I have always been faithful.

So recently I found out I am pregnant. It wasn’t planned. I am two months pregnant. Also, He’s been doing PHD so He travels for school every weekend. He has two phones one he just uses for work. So 2 days ago I picked up the phone and was just randomly going through not necessarily looking for any thing coz it’s not his personal phone. Shockingly I found out he contacted an agent asking to be linked up with a girl for sex. And he did with this phone since he didn’t want it to be linked to his personal line. He did that on two different occasions when he traveled. When I asked him he said he wasn’t the one. That his course mate asked him to do it and link him up. I know that’s not true because his friend couldn’t have been the one asking him to do that every time he traveled.

Even though he didn’t link up with the girl he was connected with , from the chats he complained he didn’t like the girl and asked for a replacement which the agent said they didn’t have .

I feel so hurt . I don’t know if I have just been sticking up and believing his lies because I loved him so much or because I have only been in this relationship nearly all my life and don’t know how I will be able to handle moving on. I am really so confused