Depression. Hands inside her dress.

I am 21 yrs male...I had ocd when I was 10 and developed sexual attraction towards mom and acted on the thoughts and would touch her inappropriately...I was treated later.when I reached 14 or 15 I was sexually attracted to my sister and would touch her inappropriately when playing and touch her body putting hands inside her dress.but would feel guilty..and I was very protective of my sister.i stopped it by 16..and did this only once or twice later..but my sister was suspicious once but never told anything..I did this to my mom twice after teen..but it was my sister who I was sexually attracted to...I did it 5 or 6 times when sister was asleep...I grew up with no exposure except my mom and sister...now I feel guilty and told this to my sister and mom they said they were not aware and consoled me..I feel like dying now as my sister was herself abused by a female when young..I love my sister and I am very protective of her but don't know why I did this.I feel like killing myself.pls help