Boyfriend

Hi, so I just need someone to talk to and vent to , and for some reason I always come on here when I feel extremely hurt. Anyway this is about my boyfriend. We have been dating for almost 4 years and we have had plans for me to stay the night since Thursday, but now he cancelled and said that he is going to a party which he just found out about today , where there will be alcohol and weed.... WHO CANCELS TO DO THAT SH*T UGHH, I just keep having these thoughts to end it because that really hurts.. Idk what to do..