I think OP hit all the right points. I am in the same boat too.
I got up to Inferno ACT 2 with the AH equipment (30K a piece, maybe 200K for weapon), but ACT 2 and beyond requires massive amounts of gold to gear at AH. Like OP said each piece of equipment is 1mil+ . I don't find farming Hell or Inferno ACT 1 appealing at all. I am tired of same old story, etc. So I stopped played DIII around a week ago. $65 for 50 hours of game play is not bad.
It's just not fun anymore. And reply like "you should not play Diablo at all, it's not for you" is laughable. It is for me, I enjoy it, but I beat it as far as I know. The last stage of "farming" and spending real money is just not for me.
Maybe if loot was better it would keep me interested, but getting 100s of useless rare/blue items is not appealing. I haven't gotten a single useful drop, every item is from AH. Might as well make all items white.