Update: He was arrested for unlawful entry into a home. She had her kids taken away. They are out of the picture.
What would ya'll do about flaky friends? I'll message this guy on a Monday and see if he wants to play pool Friday. He will say yes; yet never actually comes out. Not a bad guy. Just unreliable.
I assume he was trying to burglarize the home.
You mentioned he has debts all over the place including to known criminals and dangerous people.
He gets aggressive when you ask for the money you "lent" to him before.
His children were sleeping in boxes until they were taken away.
Take any awful person whose mugshot you see in the news, and you can find someone who vouches that they're "not a bad guy". Someone still remembers the person he was when he was young, before the drugs and the debt and the arrests... and what comes after that.
The reality is, he's not just flaky and unreliable... he's a bad guy. Think if you didn't know him and it was your house he broke into. Would you think "flaky"?
You're in an awful situation here. You are a victim of his (and her) life choices. There likely won't be a happy ending to their story. By maintaining contact with them, you're only putting yourself more and more in a position to be a target when they're absolutely desperate and no longer care about consequences.
Consider how often you hear the line "knew the victim" when really bad things happen.