Worrying & Self hate (T.W.)

Does anyone have advice for someone who constantly overthinks and worries a ton about many things. The worrying is getting out of hand, it's causing me to express more self hate towards myself. I harm myself more frequently, I stopped harming myself physically, but mentally I still tell myself how I ruin everything, my parents and I relationship, my romantic relationship with my bf, and lack of social skills, and over all not being smart for the real world in general. It's getting to the point where I've been picturing different ways to end myself, without my family or boyfriend finding out. I hate how I think like this, I want all this to stop. I wish I was different. 

For anyone who dealt/dealing with this similar troubles, I would greatly appreciate the advice, your stories about the issues you've dealt with too are welcomed here too!

Thank you :)