It is a tough decision! I had the same decision to make with my first marriage. At the time, because of my daughter, I chose to stay in the house. I felt the same way as you & wished for a fresh start.....that's what he was doing.
right? It was a struggle to keep up a house alone. But, with you & it being your Mom's house, this could make it so much easier for you financially right now. Possibly redo things to look totally different. You'll have the chance to sell furniture, buy new things, change colors & totally redecorate if you want to make the place look like a fresh start! I wish you the very best!