Please help need advice urgently!!!

So basically my partner had an affair with my cousin/sister we grew up together I was so upset andbest friends with my cousins ex and he supported my through the whole thing I forgive my partner and took him back as we also have a 5 month old daughter and long story short I feel in love with my cousins ex and we had an affair and I have now told my parner about it and he has forgiven me but there is a complication I think I’m pregnant and don’t know who the dad is and my partner wants me to have an abortion in case it the other guys but I’m not sure I want to ?????

Any advice I’m really hurting and confused at the moment so go easy on me