Problems With Parents?

I'm 18 years and i'm trying to move on with my life. My parents been fighting for years but recently it got really bad. So my mom told my dad not to tell people at his work anything about our family and my dad said he would not and so my mom kept telling him the same thing. So pretty soon my dad got annoyed and told her to shut up and then he went to his room and locked his door. Then the next morning my dad went to work and i noticed that my mom slept in longer the ussual. So i went and woke her up. She got up and stated her things she does in the day, but that night my dad asked her to go to a party thing for his work and she said yes and then my dad noticed she was acting weird, like someone would be if they were drunk. So i asked her whats wrong and she said nothing but then i noticed she took some pillls that were prescribed to her but anyways ny dad didnt go to the party because she was acting weird. So that night a storm came and the power went out and at like three a clock in the morning i saw blood in my moms room leading to are garage. So i went in there and she was on the phone and said wat happend to your are and she said nothing and they thats when i saw a little pocket knife. So i was like what the hell are you doing to yourself and she was acting weird still and so i said go to your ill help you. So i cleaned the cut and made her go to sleep, then when morning came i took my mom to the ER for stiches. My dad came home from we had a long talk with my and she said she was sorry and tomorrow would be a new day. After that my dad went to the store and i talked to my mom for awhile about all these problems she has but yeah i just dont know what to do...................I wna know how i can help my get over her problems? Its really making me streesed out.........PLEASE HELP I dont wnat her hurt I LOVE HER TO DEATH