I only wish I can give you clear cut answers and solutions; but that would be cheating you. I am also not qualified to provide advice of this nature. Nevertheless, I shall share my opinion regarding your situation. Before that, let me assure you that everyone has worldly problems, including me. Everyone's problems seems to be the greatest compared with others. At times I also feel that my problems are the greatest. The true fact is that all our problems are stressful and some don't seem to have any solution. It is "very difficult to bear", so pointed out by the Buddha. This is the first Noble Truth of our miserable existence. The only consolation is to realize this universal truth of life, and try to sail through the rough waters with all the pains and agony; and hope that with our wholesome living by pratising the Buddha's teachings, life can be a little bit more sympathetic to us.
As for your situation, the society that you live in also plays an important part in your decision. Different societies have different perceptions regarding marital problems. Some societies are more sympathetic and supportive of separated families, while others are not. You have to take into serious considerations of the welfare of your children. A lot of Asian families still stay together despite problems like yours just because of the love and for the sake of the children. Please weigh your priorities and your present situation. Let wise judgement be the teacher. Do not let immediate heartache and emotional sentiment lead you to hasty and unwise decision. If possible, talk to your trusted friends and relatives.
May you still find peace in this turbulent world.