Hi Sam, I'm sorry you are having to go through this. My first marriage broke up, and there really is no way for it not to disrupt your life in some way or another.
If you do decide to leave, it is probably best to make a secure plan before going. Get all your 'ducks in a row' so to speak. This might even be as simple as beginning to let your friends and co-workers know what is going on--you may be pleasantly surprised at the amount of support and caring you receive.
Securing your individual finances is probably the next step. Then make sure you have copies of important papers stashed away in a safe deposit box or at work.
But...not all decisions have to made today--right now. Take your time, and decide on a course of action that will be best for you! Oh, and come here and vent away as often as you need. We'll leave the light on!