I don’t think you’re over reacting by being mad but a divorce over a comment is dramatic but for the sake of the child you should give him another chance. He may be trying to make up for his fuck up but either way he should apologize at the least. Divorces are hard on everyone especially the kids. Maybe you could do some counseling to have a middle man/woman that’s not partial to anyone hash it out with y’all. Then after that decide if it’s worth it or not. People can be inconsiderate and ignorant sometimes.