Hi snow. I am sorry things have been so hard for you. It sounds like you have had a lot to deal with, even if there are no mental health issues. My parents passed away five years ago and I still miss them. It is also difficult with mom having cancer. Is she at the place where you have to take care of her? It is a challenge but yet an honor to care for sick parents.
Depression is a cruel disorder that will make you feel guilt and shame when you have nothing to be ashamed of. I wish I had a good answer to your situation, but I will keep you in my heart and prayers. You can pm me also. Love and hugs

