Though ur ex have made another gf but he might not have moved on with u. Thats very normal of him. U have got nothing to do with what whether he has moved on or made several gf or anything else. It would be best for u to deal with reality like an adult that his life is completely on a different tangent with differet goals, desires etc and ur life is completely differnet. If his new gf flirts with anybody then its her choice and that doesnt make her bad. and again has got nothing to do with u. Dont think of any false confrontation with anybody and understand what ppl do is their choice till the time they are not committing a crime. If u dont like some of their actions that concerns u then u can politely ask them to stop. if they dont then u can take some help that u are aware of already.