Misty,
My heart goes out to you. You will have to delve into your heart to find the answers but these longer-time members than me have a lot of wisdom, knowledge and strength that I would lean on if I were you.
I have put my son out in the past (both of them) only to take them back again. The anguish and pain over their emotional and physical discomfort and of course, the ol' guilt that Mom's seem to inherently have were the reasons I did.
Honestly, until I had the courage and strength (many times later and many visits from the police later) to detach from both of them and not allow them into my home, (even till this day/for now until changes that I see fit have taken place) I did not have any long lasting recovery.
What I do know is that when our "family" at the time got divided (final straw) and everyone was out of their comfort zone. Meaning, until they couldn't just sleep until 3:00 pm everyday, play video games, smoke MJ or other drugs in our home, bring all sorts of characters into our home, sell MJ to "such characters" and have total and utmost disrespect to us...nothing changed.
I didn't realize that by fixing and polishing all of our troubles, they remained hidden even by me to some degree. Until they "couldn't" be hidden any longer.
When problems are exposed, in my opinion, this can be the catalyst to begin working on making the situation better. Even if the other parties involved, like your son and my sons, don't seem to do anything in the moment to make their lives better, "we" can begin to make the changes for ourselves to bring peace and healing into our homes.
I can tell you that my life is so much better now that I don't worry the police will be at my home for some argument or altercation due to their blatent disrespect or obstruction of the law. My home is where I can pray, meditate, read good materials to inspire, uplift me and inform me or just do nothing at all. But the point is I can focus on me. Yes, both sons calls me selfish and are always angry and spewing something verbally nasty at me. I've resolved to the fact that they may never say to me someday..."Mom, I know you did the right thing" and I'm OK with that.
It's my life and I'm learning, slowly that I matter too.
I hope you can work towards that too.