@Korachanc,
This sounds like a very uneven relationship. You don't need to get an ex's side of the story-it would no doubt be biased.
You sound very together and deserve someone who contributes as you do.
He sounds like he has used you, possibly has alcohol problems and then on top of it cheated on you.
You need to let him know what is expected of him, a job, paying his portion of the bills, loyalty, monogamy, and down the line helping with parenting. If he cannot or will not do that you can bring up your child by yourself, he can have visitation (supervised if he is alcoholic), and pay child support.
I know this is difficult but he needs to do his part and you need to expect that of him or any future partner.