Do u think I need to see a therapist?

Ok so here it is. I am an 18 year old girl who just finished high school. I have gone through some hard timed in my life. My step mother was alwas hiting me cussing me. Yelling at me, etc. My dad never stood up for me. He just told me to put up with it. I lost all respect for him. But I always had my mom there to help me out through all that. She was my best friend, my world. I loved her so much, with all my heart. I was finale able to move in with her 2 years ago. And... Last year she died.... Now as u can imagine I am sad all the time. Now here is what I am trying to get at. I have always bee mentile suicidle. Een when my mom was alive. Now it is geting to where I just can't stand it anymore. U see. I hold on all my anger , sadness, frustration, etc. I hold it all in. My aunt who I am living with now wants me to go see a therapist. Do u think I should? Would it help? Would I feel better if I did?