Knowing how to be solitary is central to the art of loving. When we can be alone, we can be with others without using them as a means of escape.
During the most intense part of a major-depressive episode, what I've felt is nothing at all like sadness. Mostly, it's a kind of numbness, and utter lack of desire and will. Underneath that numbness, there's the sense that something awful is happening - there's a very small voice screaming in the back of your mind, but you hear it only faintly. There's an uncomfortable wrongness to everything, like the world is twisted and broken in some terrible but unidentifiable way. You feel numb, but it's an incredibly bad sort of numbness. This is accompanied by a strange lack of volition - if a genie popped out and offered me three wishes at the depth of my depression, my first wish would be for him to go away and not bother me about the other two. Looking back on this experience, I've conjectured that part of depression might be like some kind of mental "fire sprinkler system" - the brain just floods the building completely to keep it from burning down.
Trying to anticipate what’s best for future you will not help you make decisions, taking care of what’s best for present you will. That’s the person whose needs you can answer.