scared and guilty

Well today my son arrives with his Gf to take me 700k to his place. I got 3 hrs sleep last nite as I feel so guilty that my partner does not know I am not coming back. He wanted me to leave so I can recover from this episode of clinical depression. He thinks I'm going to be back in a few weeks and everything will resume like nothing has happened. I cannot tell him I wont be back as I don't want to create a crisis. I did tell him his pot smoking affects me along with all the other craziness that comes with it (smoker for 45 yrs). Plus I cannot live in isolation for another year..as I already have done it for four years and had 4 episodes of depression that 3 of them have lasted for 6 months. I'm so sad and confused. I do know some of my thinking is coming from a depressed mind and this is not helping. I think I have to do this to save myself Is that a fair enough call and I know this relationship is not stable otherwise I would not be wanting to get out.?? I have some support with a friend when I get there so I am grateful even when I don't feel it.