1. Counselling
A good psycho therapist trained in couples counselling will help. You may think you bicker about x and y, but there is often one underlying issue. If you can isolate it, and be honest about it, then maybe it is not the end. We can give you contacts if you need them. Make no mistake, it will be tough and draining, but it will achieve great things, even if you end up separating, at least you will have addressed that Elephant in the Room.