Kids are out of control

I need help. My husband and I have four boys that are 5, 6, 7, and 8. Two mine (5 & 7), two his (6 & 8). We've been parenting together for three years. Other parents are weekend babysitters and not even good ones. They don't enforce any standards of behavior, the kids are left to play video games and do what they want all weekend. We've tried to get them on board with co-parenting but they say there are no behavior problems there. Mondays when everyone is back home, the nightmare starts. No one can get along, no one can get back into the rules or routine. Wednesday is usually tolerable and Thursday is as close to peaceful as we get. Friday night they go to their other parents and it starts all over.We can't take them anywhere because of their behavior. 8 is rude and disrespectful, whines about everything and bullies the younger boys. If he's told to do something he doesn't like he'll scream at the top of his lungs until his dad gives in. 7 is autistic and has no social skills, 6 is a clown and will do anything for a laugh, which causes embarrassing and sometimes dangerous situations. 5 cries if you look at him wrong and 8 targets him because of it. 8 and 7 act out at school as well. 7 is in special ed services for the autism diagnosis and it does help. 8 has has behavioral therapy services at school and outpatient psych services but was discharged because he never improved. Psych told us "this isn't a diagnosis, this is who he is as a person".We've tried behavior charts with incentives, taking away privileges for misbehavior, grounding and time out, talking and explaining expectations and even spanking. Nothing has helped. I'm at the end of my rope. We've even considered divorce. It's to the point that we yell and are angry all the time. No one is happy. via /r/Parenting https://ift.tt/2Q6kvKA