I'm glad G was a bit friendlier today - but it sounds like you have him sussed now - so enjoy the remains of your crush - whilst knowing there's no future in it. You're being honest with yourself in realising that you wouldn't enjoy an affair without a relationship - I'm the same and I suspect the majority of women are. Maybe it's socialisation, or maybe it's the way we're wired, but it's hard to do the physical thing without actually liking/loving the guy's mind - unless you're very, very, very drunk .
What you've said about you being h's first partner etc chimes exactly with what I'd begun to wonder about your situation the last couple of weeks (I've been thinking about you even though I haven't been online much). Your h is obviously afraid of losing you, but he himself isn't secure or psychologically mature enough to realise that the only way to keep a lover is to let them be free (the old cliche, but it works!) The trouble is, he may never learn that within your marriage as it's a pattern he's been in all his 'adult' life. And you, you can have SO much more. There's a world of men out there and you have your work and ds and hobbies and friends as well!(The advice I give my DD, now that she's 15 and may fall in love any day now, is never to settle for the first man she dates - or even, maybe, the second, unless they are mature enough and man enough to let her be herself and support her in following her own 'bliss' - it's rather the opposite of what my mother advised me, but then she came from a pre-war generation plus being brought up in an Asian country where even though her own family didn't do arranged marriages, they still tended to marry the first respectable middle-class person who asked!)
Does your H have many friends or other interests outside work and home? I would have thought that if he did, he'd notice that other men don't necessarily expect a home-cooked meal on the table every night, even when their wives are SAHs, nor is a clean and tidy house the be-all and end-all of existence (children develop better immunity with a little dirt . I say this as a woman with a major cat hair problem on her carpets, and yesterday's leftovers ready to warm up for tonight, but at least dp seems happy with it (and when the cat hair gets too much, he knows where the Miele is!)
Sorry, I'm rambling on again - but I do think that ok you suffer from depression and all, but I really think the problems stem from your H's inability to realise how to run a modern shared relationship in the 21st century. However, you do !