regularMMposter, how awful for you. Sounds like hell in a hand cart and I know it would break me to hand over my beautiful children for someone else to enjoy. Numbing out some of the pain is totally acceptable.
However, its like putting off a phonecall or ripping off a plaster, you are probably going to have to look life right in the eye at some point and face it head on. This will be when you are ready.
IMHO there are two ways to change:
(1) stop drinking completely
(2) cut down
You'll know best which will work for you.
When you are ready to begin plan it, in your head or on paper. You may have to hand over your children to exp but that doesn't mean that he and his gf have control over your life. Can you fill the time they are away with something that will make you feel good? That way, you don't feel like you've been shit on, you feel like he's babysitting for a little while. Then, when your kids come home you are feeling good about yourself and thus they will be delighted to see you.
I by no means mean to lecture you. Its just I spent a long time feeling rough these past few years (not through alcohol) and I have lately begun taking more care of myself and have put myself up the list of things to do. I am feeling really, really good about myself and strong again. I started in a small way but the key is not to stop, just keep building.
When you are down, everything is down. When you take control it has a knock on effect on every part of your life. Only you can do it and only you will know when you are ready. I am glad I wasted no more time feeling crap. Good luck xxx.
p.s. you are not pathetic, you are just fine and you will change.