Separation During Marriage.

My husband and I separated earlier this year for around two months or so. Just when I had become okay with our separation he slept with someone, and it hurt because I felt like we could still work on our marriage. When I found out by an outside person that he had been with someone else, I decided I should try to do the same thing and figured it may help. It did for the most part, then the husband came back. Begging for another chance, so I gave him one. We are still together and I am 9 weeks pregnant. Could be the man I was seeing or my husbands. My husband wants to stay regardless of who's it is, but doesn't want me to tell the other man. . I respect myself and would like him to know but I also feel the need to respect my husband.

I guess I'm just looking for advice &or suggestions.