does it count as cheating?

[student-life]

i had been going out with my girl friend for 3 months. it was the best rleationship that id ever had. everthing was perfect until i went on my holiday and her friends told her to talk to her ex bf, so she did, then met up with him. apparently she never did anything. it has been 3 days since we split up. we met at a party last nite and hooked up there but avnt rly spoke since as we wer both drunk. im goin to this party 2nite with anova girl, i could pull her and prob get laid but dont no if it would ruin the chances of me gettin back with my ex.i dont want to ruin my chances with this girl if my ex still doesnt want a relationship. is it worth it as no1 she knows or i no is goin to be at the party?