Idk what to do

I'm 19& 33 weeks pregnant by a 33 y/o man who is engaged .. When I first got with him he told me he was single and everything was fine until he went to jail ,That's when I found out I was pregnant... We talked everyday for the first 6 months of my pregnancy and when he got out we seen eachother and talked & that's when he told me he's getting married next year ! He wants to be involved in my child's life.. But wants my child to be a secret.. Because he is marring the mother of his other child an is scared she will not let him see his other daughter .. Idk wether I should let him be there for my baby or just let him go .. We still have sex and he calls me everyday asking about me an our daughter .. An wanting to come over and you know what.. But he switches up when he's with her an I don't want to be the "other woman" . But I want him in the life of my daughter an he wants to be there I just don't want my child to be a secret.. I just need some advice should I just block his number and move on ?or allow him to be in my child's life as a secret child that'll never know his side of the family ...