Marriage is going south. Please help

Okay so I'm posting anonymously because I know people are saying I shouldn't be doing this. But I'm asking please no hate or rude comments.

I understand a lot of you wouldn't have gone the route I went. And that's fine but please don't bash me for trying to save our marriage.

My husband and I are taking a break because of some recent events

Our fighting has gotten really really bad and I know we don't mean it but were both hard headed and stubborn.

I've started fights and did some questionable things

And so has he.

Recently he has cheated on me with my friend who was staying with us. He regretted it and told me as soon as he could. (Our a.c. went out and me and the baby were stayin at my moms)

I have since kicked her out and when I asked why, he said he fell in love with what she wasn't doing. (Fighting with him, yelling, etc.)

He says he doesn't know if this can be fixed because of the fights and his fuck up with my friend.

I do know if we do fix it..we are both going to have to work extremely hard on both sides for each other. My question is , what kind of things little things could I do to make things a bit better? I'll be the one to admit I haven't treated him the way I should have. And if I wanna save this I need to step up just like he does.