SAHM when my 1 yr old boy sees his dad he freaks out and wants him

It is nice but also gets me feeling like, does he want him more than me? Is it just cause he sees me more because I am with him all day so when he is with his dad it’s more special? Husband also cheated on me and found out recently it happened all year and I am pregnant. I guess I am just hurt so now it bothers me and I just want my baby boy to be a mama’s boy and I am having another son in a few months…