When do you get out of a marriage to an ADDspouse

We are in our 8th year of marriage, with 2 children under 6. My husband was officially diagnosed with ADD when our son was 2, his is co-depression. He has had at least 18 jobs,  one third ending in two weeks, the longest job he held was 9 months.  Most of the time we are not insured such as now. I haven't had a regular checkup in about 3 to 4 years.  I have the children insured through the state which is now being terminated since my ADD husband forgot to put the envelope they requested in the mail. One of deals, was he is to fix part of the mess he makes. All he had to do was put it in the mail. Both children need speech therapy, but money allocated for medical has always gone for his doctors, Yes four years of therapy, coaches, lists and medicines have not improved his lack of organization and time management. Two of the biggest reasons he loses jobs.  He is also quite arrogant, this has cost us bundles because he believes he is smarter than all others.  The sad thing is he has a masters degree and is professionally certified and he has been sober for 15 years.  He has no recall or common sense and sometimes it is not ADD, he is just lazy.  I work part time at my children's preschool and have received aid to pay for their school. We have little debt because I manage the bills and although we live in a old townhome, we will not lose the house. I have given him until June to write a plan and put it in action, using all the advise he has previously ignored. He has to secure a job any job. I am sure I am depressed but really do not have the time or money to pay for me to go to anyone.  My children watch more TV than I want them too because I spend the afternoons cleaning the house and fixing the messes he makes.  When does marriage with an ADD spouse become more hurtful than helpful?  When is the best time and way to separate from the chaos and unstable enviroment?  When is a marriage to an ADD spouse bad for the children? Does anyone have any advise or examples of what I would face after the divorce?