Personal Stress vs Nursing School

So, I know I am not the only person who had had marital problems, but I feel I need tips to see my way through school without letting my personal life destroy the hard work I have done to become a nursing student.
Just after I was accepted, my husband and I began to experience marital problems. I am in pain over our situation and it really messes with my concentration.
We are going to begin counselling, but I am afraid things may not work out for us. We have two children who I don't want to see hurt and I have hopes for a nursing career so I can grow as a person.
It is hard to get focused on school when I just want to dwell on us and putting our marriage right, if we can.
We have both made terrible mistakes.
I am experiencing a lot of anger!
What have others done to keep their energies focused on succeeding when the rest of their lives seem to be failing?
Thanks for any advice.