I can't stop thinking of different ways to take my life, please help.?

Okay, so my Dad was diagnosed with Biplolar Depression, Manic, with Psychotic Features. He took his life after 8 years of dealing with it, and I've been depressed my whole life. I constantly cry for no reason, I also have panic attacks around people, and I think about suicide ALOT! I stay in the house, because it's gotten so bad. I can't be around people, or I just cry. I've tried to be closer to God, but that hasn't helped my depression at all. I feel like I'm stuck with all these feelings and emotions because my dad was the same way, and I don't wanna live like this anymore. I'd rather be dead, than live everyday of my life sad and thinking about being dead. I'm only 19 years old, but this has been going on my entire life. and my Step dad and the rest of my family, make fun of me because I act so different, and my mom always tells me I'm just like my dad. I can't even spend time with my friends anymore because of my Depression. I've also ruined lots of my relationships because of it, I'm starting to think I'll never be happy. My life is going completely downhill, and I'm scared, because I can't control this, and I don't know how much longer I can put up with it. Anyone have any advice? I don't know what to do anymore!!