My baby mama and me live together with her 6 year old daughter and our 5 month old baby. We fight constantly, we rarely see eye to eye

And we can’t have a simple conversation without arguing. Her daughter got transferred from her old school a few towns away to the one in my area and she loves it. We try to keep things alright but we can’t no matter how we try. She told me last night she doesn’t know how 2 people that love each other and understands that they have chill out and quit arguing about stupid things and pick the battles but can’t. She has a problem with pretty much anything and everything I do. Also, she just got divorced by her daughters father. Anyway I asked her last night if she still wanted to try couples counseling and she said there would be no point it wouldn’t help and I said since she feels that way and doesn’t want to fight to be a happy family we need to plan where they’re gonna go. She said she needs me to be the one to make them leave cause she wasn’t gonna be the one to take her kid out of school again and do that to them. (the house is mine and only mine btw, she lives here taking care of the baby and isn’t working so it’s my income only) She refuses to find a place to go, says there is no place to go (which there is, her parents house 45 minutes away) but anyway, I’m not kicking out my own baby, a 6 year old and their mother. Out of all the girls I could’ve picked to get pregnant it had to be this one.. wtf. Any input would be nice. Thanks.