Dated for 4 months, She found someone else in 2 weeks

I dont really have the energy to explain every detail right now but I'm 18 she's 17. We were long distance, we called every day and night for 4 months straight. Everything was perfect. There weren't any issues I was aware of. Usually I notice every little sign of her losing interest but this time there weren't any. Then randomly one day she said her mom had an issue with us being long distance. But she still said she loved me, we just couldn't date. Today I saw her on as another guys GF highlight. Texted her about it and she told me to move on and downplayed our whole relationship. I'm just done with life she was my everything. I really just wanna sleep and not wake up. I need help. I don't know how I'm gonna make it she was all of my motivation and purpose. I have nothing and no one to distract me.