I don't have personal experience of your situation, but I have had friends over the years that have, and I've seen how liberated and how much happier they feel when they finally set themselves free.
I'd also say, given the ages of your children, that now would be the best time, unless staying for a short while longer would make a big financial difference to your life after. I think separation/divorce can be a lot harder on teens because they have so much upheaval of their own going on, without having to deal with family stuff as well. Obviously many will be fine, but give the choice I'd say better to do it with a ten year old than wait until the the dc is pre-teen/teen.
This is enlightening too Dads the fun one and i'm a miserable bitch, being passive agressive because of the resentment inside. You have time still to show your DC the real you, the fun you, the happy and contented you. They will have picked up on your resentment, the example you gave is, I'm sure, just one of many instances where they will have sensed that. Another good reason to go now, so that you will still have a good few years with them before they are off to uni or leaving home, to let them see you happy. In two or three more years your eldest dc will be at the living in the bedroom and only coming out for food and friends stage. Don't leave it until them, as it will be so much harder to re-engage with them.
In all honesty too, although he's not your priority, you've said your H wants more from his relationship, so it's not really fair to let this drag on for further years.