My post is likely to be the first (or one of the first) of many, and they are more likely to be from people in your own situation (I'm a single bloke, so take anything I say with a pinch of salt), so I shall keep it short.
But, in a nutshell: We've all been there, and you will feel better. I promise.
At first, you are sure to spend your time thinking back on what you lost in your previous life. You will want to surround yourself with things from home, watch telly from home, speak English and so on. My own arrival was beset by difficulties (new job, new flat, new country, just been dumped by the fiancee for whom I'd upped sticks in the first place), and I had a desperate need for contact with English people and things (to the tune of a 2000 CHF mobile phone bill for my first month here).
Gradually, however, I came to realise that all this weird foreign-ness was an opportunity - a long holiday, if you like - and a chance to do something different for a change. I understand that with children, to some extent you are limited in your options (I was all alone out here, so the loneliness was balanced by independence), but there are many other people out here in the same boat, with whom you can share trips out, coffee on the lake, walks around town, trips to the chocolate factory near your house, and suchlike. Get out there, and enjoy living on the side of a lake, near the alps, with a chocolate factory down the road (you can almost hear the envy as I type, can't you?).
Perhaps you can enrol your children in an English or bilingual play group or nursery? They'll get to have fun, and you'll get a few hours to drink lattes and shoot marmots (or whatever you like to do). At the very least you'll meet other English speaking moms.
And finally (I did promise, didn't I?), try and make some effort to learn the language - some people thrive on classes - others, like me, prefer to just blag it - either way, you'll start to feel better about yourself and your abilities, and you'll have more contact with the locals who are generally alright, considering they're all foreign...
Anyway, good luck, enjoy the responses you will get on this thread, and chin up! It really does get better. Honest!
EDIT: Longbyt says it better here: Tips for Trailing Spouses