He moved out...

Though he has not been diagnosed with ADHD I feel pretty confident my husband suffers from it. He has never been able to reach his goals, feel self confident, hold a job, maintain relationships, or in general, have any kind of focus on anything other than himself.  I gave him a couple books to read, hoping he would come to the conclusion that he has ADHD and get some help.  Not holding my breathe, but I am hoping he has some sort of an epiphany. 

After 24 years of marriage...me supporting him both emotionally and financially...he moved out. He started sleeping at his 'office' a couple nights a week, then more, then eventually stopped coming home.  (His 'office' is a room in a condo that he rents - and pays for out of my salary. He claims he is doing some marketing work there but does not make any income.) 

My problem now is whether I keep financially supporting him while he lives 'on his own' and figures his life out.  I pay for his rent, food, gas, insurance, cell phone, and multiple gym memberships.  I also pay our mortgage and all my own expenses along with expenses for my child and our pets.  Really, I feel like a chump. I don't wish him any harm but have no idea how he will survive if I start cutting him off financially. We made this mess of a marriage together but I am so very tired of doing all the work with no return.  I am ready to take responsibilty for taking care of my own life but can't do it if I have him as my 'dependent' adult.

Can an adult man with ADHD who has never held a job for longer than a year be self supportive?  Will cutting him off financially make him 'worse' or make him go off the deep end?  I believe our marriage may be damaged beyond repair but I want him to be able to have a good relationship with our child.  How can I help him do that without getting sucked into supporting him for the rest of his life? 

Anyone have some advice for me?