So let me get this right.
Your constantly fighting, he is accusing you of cheating.
Calls you a *****, you fight all the time.
He texts this other woman who you believe he has cheated with and won't stop contact with.

And your reason for not getting married was financial stability!!

Hon,I can see a hundred reasons you shouldn't be married.Financial stability doesn't even rank amongst them.
I have zero idea of what you hope to achieve here, cos this thing was a wreck before you signed the papers.

Pity on the kids cos this isn't the example of two people loving each other that shows them how to build healthy relationships.
Stop the title for that, get counselling or get a divorce.
Make it work or accept it won't. But don't waste more time than necessary asking questions you know the answers too.

I wish you all the best, and hope you find happiness in your future.