Am I really done?

Saw another (awful) therapist last night.  Ugh.  Trying so hard to stay within my insurance network because it would be a financial hardship not to.  But, these people are not ADHD experts.  Or anger management experts.  They say things like "Count to 10" or "just breathe" when my husband talks about his inability to stop an outburst.  That doesn't help him.  We want so badly to stay together, but now we are starting to use words like "separation".  That scares the hell out of me!!!  And I'm the one who brought up that word.  Because, after 13 years of marriage, I am spent.  Our son has ADHD.  My husband has not yet been diagnosed, but I'd bet my life he has it, and he also believes it of himself.  What do we do??  When do I know I'm really done??  Do I go to a so-called ADHD expert and spend $400 to get him a diagnosis and hope this person gives some good advice in the 45 min time slot?  He wants to change, but what if this is just part of his personality?  I feel like I have completely shut down.  That has been my defense mechanism every time he has an anger outburst.  Only now, I've shut down permanently and I don't know what to do.  I feel like I'm on a train and I can't stop it.  I can't stop my feelings of hopelessness and I can't control him or his angry outbursts and I can't control what's happening to us as a couple....  Feeling very lost here.