How do i stop hurting? (long story, bear with me)?

i don't know what to do to stop hurting. i'm 19 years old, a senior in high school. i've been living with my dad for alittle over a year, he and i were very close in the begining. he was recovering from a crack addiction and alcoholism and doing very well, he had a few relapses during that time but they consisted of getting high or drunk once, telling me about it if i didn't already know, appologizing, and then stopping and staying sober for several months. about 2 1/2 weeks ago he and his live-in girlfriend had an arguement and he came to me and said it was about him using behind my back for several months. he told me he would sober back up and things would get better, i didn't believe him this time, about a week later i found a crack pipe in a cigarette pack while he was sleeping. i wrote him a long note telling him i needed to get out of the house to think and i didn't know when i would be back. when i got a hold of him again i told him i didn't think it was healthy ... to be cont.