My parents argue all the time. It has gotten worse with each year since retirement. Is it okay to suggest and pay for counseling for them?

They are in the 70s and my grandmother just moved into a nursing home. I have suggested that they all move closer to me but they refuse to sell their home. My mother's solution is to have my Dad stay with me so she can keep his income to support the mortgage of their house. I find this ridiculous. I really am at a loss on what to do.