Was with boyfriend 5 months and he would only stay over night once a week

He lived right next door but only stay overnight ....then I broke up with him and the same day he was with somebody else and he stays with her every night!I think that's where he was at when he wasn't with me.he says he barely started seeing her the day I dumped him

Not even a question, slam dunk he was seeing the other girl whilst seeing you. It takes time to build enough trust with someone to stay overnight with them so he had to of known her for a while. Most likely he was seeing the other girl whilst dating you, sorry girl.

I know and he used me for money and I cooked for him bought him clothes whatever he needed and fixed his truck and he'd act like it was so terrible just to spend a night he'd leave right away sometimes he's like I'm busy playing video games or at the bar but with this person he stays with them all week everyday

I'm so sorry for this honestly. You didn't deserve it. The only thing you can do now is use it as a lesson next time, ensure that your efforts are being reciprocated by your partner before spending all your money and giving up your time on them. OR even before you start dating that person, make sure you see evidence of them at least showing you good enough attention and sacrifice before fully commiting.