I know most people will say to just go find someone else but's hard when it's your first love and you've been together for 6 years.
I can really sympathize, since I recognize myself in this. I got together with the third girl I've ever loved, the first one I had a shot with. And in hindsight I should have know long before it did end that it wasn't a good relationship, at all. But I held out, I ignored things, explained things away to myself and so on since I thought "This is my chance. I'm not getting another one." Which even though I am down on myself a lot of the time, is of course stupid crap.
And if you want to be cold about it, let's put in these terms: you're obviously giving him more then he's giving you in return. Both emotionally and financially. And that's not a good equation. Says the guy who hates math.
Hope whatever you decide works out for you.
Oh and
Drone. Yeah she's a great gal, but at least I am not the kind of scum that would give someone good advice to try and exploit it. Give us some credit.