It sounds like you're in the thick of a rough patch. Divorce is an option but brings a whole new set if issues with it.
When the DC are really little, like your youngest at 1, life dan be a bit mundane. Going out for a meal or evening out is either a faff with tired children in tow or a big event involving organising babysitters no doubt tidying the house etc etc.
I also think the adjustment shift to being a parent takes quite a few years. As a big generalisation I observe that the less hands on parent, usually Dad, just doesn't appreciate the level of little endless tasks that need doing with young DC and how all absorbing and frankly mindless this can be. I think as children become clearer communicators at 4/5 the less hands on parent is able to interact more and get more back from the relationship.
I think its quite easy to find life quite depressing and restricted with children at that young age. I did divorce when my DC were 3 and 1. We had a very cold winter, forced to sell house, no benefits due to a cock up and had to borrow money for every bit of food, bill that came in. XH shacked up with OW and berated me for not having several winter coats for the DC when he missplaced the ones I'd sent with them, critisised me constantly for all sorts of things including my appearence. It was worse durring divorce than before. It wasn't an option as he was in love with OW. It took years to create stability for the childen.
Rather than what you don't want why not focus on what you do want from your life?
Do you want more nights out, to join a gym, to have more time to yourself, a better division of house chores, more holidays, less responsibility for all things child related? Once you've fathomed the sort of life you'd like have a think if actually its achievable within the set up you've got.
Look at your DH's strengths - money, faithfullness, stability. Sounds like quite a good set to me.
Crap at organising DC's birthday presents, well in a year or two they'll be writing a list he can work from so that'll cease to be an issue.
Crap at birthday parties - well if he's earning a fair bit and hates the party why not ask if he'd rather pay for parties out and you do the minimal supervising involved. He can just enjoy cake at the end or even at home with just family.
The little snippy remarks need work but you may find if you're finding more outside activities to do yourself that you are able to positively tackle these too. There are constructive ways to handle moaners and moaning is a trap that we can all no doubt fall into are you sure its all onesided?
Long and short - stop take a really good look at things, divorce is a big step for when all other options have been explored.