My mothers (40f) partner (44m) is a nightmare.

They’ve been together on and off for about 6 years now.

He cheated on her after they got back together for 1 year or so. That was 2 years ago now. He has a history of doing this to his past partner who he had kids with.

Long story short, we VERY HESITANTLY brought him into our home (me, my sibling and mother) because his life was in danger and his reckless actions led people to want to hurt him. I begged my mother not to let him, I heard her out with the “he’s changed, you have to let go.”

I’m 18 and living at her home.

I wanted to be the bigger person and accept that we all make mistakes and will continue to make mistakes. The “it’s not how you start, it’s how you finish approach.”

We let him into our home, me and my sibling would be very anxious around him for the first month. Then after we became ourselves.

The main issue is that he doesn’t understand the impact of his words, he is degrading, hurtful to my mother out of what we think is spite, jealousy, random.

Some incidents are:
-When my mother got her new job with a huge pay difference from her past one, huge perks, lots of downtime, etc he said that “this is why people like you will never succeed in life” because he was talking about her drinking habits.

– As she is now enjoying her money around the festive season she can not worry too much about upgrading our home. I’m loving it, she’s buying a. new couch, new TV, she’s able to feed the home without worrying, she can buy gifts for the first time in years for me and my sibling.

While she was out with him, he watched her struggle to carry heavy bags even though she asked him to help carry them. And then proceeded to make comments about “why are you doing this. You’re spending too much money.” And “they don’t deserve it.”

We’ve open our home to him when no one else would, even his own father. We’ve genuinely done nothing horrible to him. Maybe we gave him attitude in the beginning but idk why he’s so spiteful.

Also, this person has lots of money and spends hundreds maybe even thousands on his own kids every time they ask for something. But is hesitant to give my mother even 30 bucks, food for the whole house or to contribute to the home at all.

I know it’s not his home but I just started working and I’m making sure to give my mother 50 bucks, pay for any appliances that need fixing/upgrading, 50-200 bucks worth of groceries each month. Because I appreciate her, my family and most importantly—because I WANT to.

There’s many other times he’s hurt my mother but idk what to do now. She keeps allowing him to stay here until he officially moves. He’s found a house and he should be out by January.

I don’t know how long I can play this forgive and move on game now.

Sorry if there’s a or of spelling mistakes, there’s a lot of lag.

TL;DR: my mothers partner is ungrateful, stingey, spiteful, hurtful to her (and us) and cheated on her a few year ago. He now lives in our house and She can’t stands him but struggles to cut him off (not because of him but I think her worry of being alone?).