Why do you love me?

I'm a real sod to live with. I've been having a rare episode of navel-gazing, which unearthed the following truths:

I have 2 gears -

1) full-on caffeine-fuelled manic - I drive too quickly, walk too quickly, eat too quickly and talk too quickly. I do everything at 100 miles an hour. I get palpitations and heartburn. I have a resting hand tremor. I talk to myself and laugh madly at random things that no-one else thinks are funny.

2) catatonic staring at the TV or engrossed in a book - I am utterly unwilling/unable to communicate with anyone or engage with the real world. A slack-jawed, dozy sloth.

I cannot tolerate anyone disagreeing with me. When annoyed I swear a lot and raise my voice in an attempt to browbeat the other person into submission.

I have a phobia of organising things and planning. It makes me stressed. Difficult when your boyfriend is on the OCD side of the spectrum.

I'm a bit of a slob. I get home, the place is a mess, I notice the place is a mess, but I really cannot be arsed to do anything about it and so flop on the sofa with a glass of wine instead. Fine when you do it once in a while, but every night is a bit much for the person you live with if they have a lower 'mess threshold' than you.

Mood swings. Sometimes I'm inexplicably happy, cheerful and smiley. Then I'll suddenly start to go on a downer, often triggered by something very minor (or sometimes by nothing at all), and I'll feel like crap and get snappy and sullen. Like this morning. I woke up feeling horribly anxious and stressed out for no particular reason, then burst into tears and refused to get out of bed for half an hour. I was late. When I got to work I felt strangely serene and was in a pretty good mood for the rest of the day.

Pessimism - I always imagine the worst possible outcome, just so I won't be disappointed if/when it happens. This could be taken as realism/pragmatism, but I work myself up into a hyper-anxious state and convince myself that this is how things are going to turn out. Usually they don't, but I do it every time.

Short temper - I get annoyed so damn easily, say horrible things I don't mean and then cool down soon afterwards and feel awful about it. I sometimes make a conscious effort not to bring something up that's annoying me, as I realise it's petty/minor/silly, but then it inevitably builds up and up in my head until I randomly explode and make much more of a fuss about it than I would have done if I'd just said something to start with.

It honestly puzzles me deeply why any man in their right mind would want to go out with, let alone share a house with, a person like me. I wouldn't want to live with me. I'm impossible. I have insight into this, but can't seem to do much about it. I do try (intermittently) to behave like a sane, rational human being, but unfortunately I don't happen to be one.

I do love him. Very very much. But I worry that he'll get fed up and leave. Or worse, meet someone who's sane, fall in love with her, and then leave.

I really must try to stop being such a total arse.