ADHD is running my family into the ground

I am new to the whole research thing and have had a long haul to get here.  My husband has ADHD and is very aware of his diagnoses.  He has sought out medication but no real support.  We have been in marriage counseling several times but never addressed our specific issues instead focusing on issues with his mother, of whom we are both sure is undiagnosed, We both work full time and until recently were both home at night with the kids.  My son is 8 and we have run the gauntlet with him.  He has been asked to leave several daycares, has been in a couple of private schools one of which allowed our daughter to stay but would not allow our son to reenroll.  He has been bullied at school but because he lashes out to defend himself he is punished.  He doesn't understand when he does something wrong.  when asked he truly can not tell you why he just thinks everyone is after him and hates him.  We have put him on medication which has helped in the classroom to get him caught up in reading.  He is a really strong math student.  He doesn't understand why no one wants to be his friend.  At home he lashes out at me and has a cutting tongue.  He is cruel to his older sister yet can turn around and be the sweetest kid.  I have boundaries and discipline set but they do not seem to work (daddy doesn't follow them at all).  My husband like my son is very confrontational they both think they are right.  They hardly argue with each other but to me it seems like they are picking a fight with me.  My husband is quick to criticize me with money picking up receipts and questioning me about every item on the receipt yet he has no problem pushing the envelope when it come to due dates with bills.  I am the only one in the house that keeps everyone on track as well as hold down a full time job.  This is beginning to take toll on my health.   I have developed anxiety and was recently diagnosed with fibromyalga.  The walls seem to be caving in.  I do not know where to start. Please help!!!