I was in a similar spot a couple of years ago, and it ended up with divorce-
I'd just graduated w/my masters, landed a great job, and was starting to get very competitive w/cycling. He was still stuck in dead-end jobs, making poor financial decisions, and generally trying to be miserable with life. Like you, when we first got married, we were great for each other- we were both struggling a little to get our "stuff" together, and we helped each other out. Problem is, I matured, worked hard, and succeeded, and, though he was fully capable of doing the same thing, just couldn't seem to find the motivation. So I decided I'd be better off on my own, and I've never regretted that.

Not saying that you should/shouldn't do the same thing... just giving my experience!