It sounds like you know the answer to your questions but you don't want to hurt others. There comes a time when you just have to put yourself first. Everyone else will adjust if you focus on your long term happiness as well as theirs. Children will of course want a happy home with both parents but sometimes that means a happy home with one parents if to preserve their happiness. They wouldn't want you to be unhappy! They just fear the change. You too have to find your happiness and act on this. If you have reached a point where this can't be repaired then therapy isn't the answer. Marriage counseling is always available for those interested in fixing a relationship but not if you know that you heart isn't in this. Counseling can change the dynamics but it can't fix a broken heart. Decide if there is no way back to a relationship conducive to your happiness and then act! Before you act on what other's want, act on what you want.