BIL from Hell

If this was your brother in law, what would you do?

I have been with my SO for 5 years consistently. Theres been no break ups, no cheating, or anything that would make our relationship look inconsistent. We just aren't engaged and have no children. I mention this because my BIL and MIL don't take me seriously at all. They think I'm temporary.

Throughout that 5 year timespan, his brother has been a toxic person in our lives. He only wants us around if he needs money or a favor. He constantly insults my SO and myself. He makes up stories and makes himself out to be the victim to my MIL so she'll be sympathetic and take his side. He's broken into our house, threatened to break in again and at the same time threatened to beat up my boyfriend or me if I happened to be home and we tried to stop him. He's even trashed our house before while we weren't home and left the doors and windows open so people could come in and take our stuff.

Recently, He tried to trick us into giving him "rent" money but we said no. He then tricked their mom and uncle into giving him the money and went out and bought his baby mama an engagement ring with it.

He calls my SO from phone numbers other than his own and cursing and being aggressive so they can "hang out" together. But because we dont like each other I'm not allowed to go. That makes me uncomfortable because when I'm not around he tends to start arguments with my SO, talks shit on me, or tries to get money out of him.

When my SO stands up for me, himself, or tries to call out what the brother does wrong, the brother threatens to cut himself out of my SO's life. Except now it's worse because he won't let us see his baby.

We want desperately to be apart of our nephew's life but it's almost impossible with the brother being so aggressive, manipulative, & cruel. My MIL does not take our side or understand where we come from at all and is of no help to us.

Would you ladies try to suck it up and be cordial? I've been standing my ground and saying the brother isn't allowed near our home, that my SO can't go without me, & we can't give him anything other than time. But damn the constant conflict is just killing me. We just want to be apart of our nephews life. Any advice at all?

Sorry it's long and I'll try to answer questions.