Being alone to soothe yourself is under-rated. It's okay.
A thought: therapy that involves the family has the highest rate of success. Especially if the family is what's called "over-involved"...which means they try to take over for the borderline. Even though you are not at home much, it's worth suggesting to your wife that she and the kids get therapy to support themselves and you.....I wonder if that could be arranged? It would take some of the pressure off of all of you. And pressure/stress often is the source of depression and dissociation.