All couples argue if you want your family to work talk to him. Let him know communication is key and having a child puts so much stress on a relationship. Just remember all couples have their ups and downs its all about how they handle them. Even couples that have been together 50 years have probably been where you are. Stay positive and keep fighting for your family it will all work out:)
And maybe if you havent already, reach out to him, especially since you say you guys broke up, if you do want it to work out.
You both are under a lot of stress with 2 little ones. The arguing needs to stop. Instead let the small things go and only address the important topics, one at a time/day or week. And try not to get emotional, keep a respectful tone and pick the right moment or opportunity to address things, preferably not around babies. You'll see a big difference between you both if you do this, trust me. At least thats been my experience.
Talk to God, Im sooo sure, He will help U or show U the right thing to do, I say it cos He has helped me sooo much where others just cant help! God bless You!
If he wants it to work yes. I would suggest counseling if you guys argue that much but want it to work. I don't know your religious beliefs but many couples find church helps too.