You know, the decision is ultimately yours to make and all I can offer is advice that will definitely have my priorities set in it ... so please take this with a grain of salt.
My initial reaction was that if it had been myself in your shoes; he'd no longer be in my life. While it is difficult to remove yourself from a situation like this where there are a lot of emotions involved; it's not healthy to be with someone who so clearly ignores your security blanket and comes up with every excuse to justify doing so.
When my ex-husband and I mutually decided to divorce, my biggest worry wasn't for myself, but for him. He hated paying bills, doing chores, basically doing anything and everything that has to be done. I worried he'd fail and fall and I decided that the best thing for me was to move to another state. It wasnt' even because I was still in love with him that I worried. I felt responsible for him as I'd taken care of him for so long.
You have a decision to make and it's simple. Either you stay and continue to be the only one trying to make it work OR you leave. How you arrive at the decision that is correct for you will be the hard part. But you will find that once you've made the decision, the rest gets a whole lot easier.
I wish I could hug you for real.
If Plan A fails, remember you have 25 letters left!