Hey there. I've been in a similar situation and I can definitely relate. I've always known I was intelligent, but I had lots of insecurity as a child. Largely (I realize now) due to a narcissistic mother and divorce issues. My Dad (while having his own issues ) was my life-line. As I got older we got closer. When he died 11 years ago, I spiraled down for 2 years into massive depression.

But it got better with meds and counseling. It still gets bad sometimes, but with counseling and treatment it can continue to get better. It is a continuous process and sometimes it's hard work. But as @Syra (What's up California in the house!!!! ) said if you felt better once, you can feel better again. Hang in there. I know its hard.