you walked out on him? fairy, you removed yourself to protect yourself and his child. any 'good' man who made a 'mistake' - which is how you are describing him - would be absolutely mortified that he had done this, and desperate to do anything to win you back.
For example - if I , in a fit of rage, hit my boyfriend and he walked out - I would be so desperate to prove that I loved him and that I would be a good partner to him - I would be on my best, best behaviour. He is pissed off with you???? this is a joke fairy - I really really wish you could get the self confidence to be angry with him for this - I hope you can.
Please, please give yourself the space to think about this with professional help. did you grow up in an abusive home? I wonder why you think that his behaviour is acceptable.
you say - if you all came on here and wrote the bad side of your DP's we'd say leave - no. My Dp's badside is that we argue about tidying up and he is really clean and I'm not. He has never punched me. that is NOT normal or acceptable.
how DARE he be pissed off with you. Fairy, the real man has come out here, he is angry that you are resisting his control. He hit you - he should be deeply, deeply ashamed. Instead, he went off and slept with someone else and is now having a go at you - his wife - for protecting herself and her child.
please, just give yourself space here to see all of this. a good man would understand that you need to create distance. A good man would respect this and work with you on building the relationship up.