ADHD getting worse with age and retirement

I'm new to this forum and so glad to have found it.  My boyfriend of 3 years has ADHD and knows it, however, I'm not sure it was ever medically diagnosed and I know he's never received treatment for it.  He retired from a successful business last April and is progressively getting worse with his symptoms and behaviors.  I've realized that before he retired he had several employees to take care of many of the things he's having such a hard time with now, and he had a schedule which helped, even though he's chronically late to everything.  I also feel like he has so much less interaction with other people now that the weight now falls on me to be everything to him.  I'm about worn out! I've realized that he/we need help!  I was the enabler in a co-dependent relationship with my exhusband for 10 years and I fear that's where I'm headed again in this relationship--keeping the peace, going along, denying my own wants & needs, etc.  That's not how I want to live.  I'm praying for the right opportunity to raise the topic of him getting help, praying he'll be receptive.  He's overly sensitive to anything negative coming from me, reacts with quick anger, he's more frustrated than ever with life, he's developed some obsessions such as working out 3 hours a day, we are arguing for the first time ever, and he can sense that I'm pulling away, because I am.  Any advice?  I feel it's at least worth trying to talk him into getting help but if he refuses or says he will just to get me to be back off then does nothing, I'm not willing to continue a relationship like this.  I'm close to the point of no return.