My ex-boyfriend is trying to use my friend to hang out with his new girlfriend?

Me and my ex broke up about a month ago on bad terms. We had a long relationship and he cheated after 8 months together. I was heart broken and still am. While we went out my friend went out with his friend so we used to go on double dates. My friend still goes with his friend but my ex has a new girlfriend. This new girlfriend also is the girl that I hate for other reasons. My ex asked my friend to pick him and the new girl up so they could double date. He told her it will be like old times just dari won't be there so we can actually have fun. She told me about it and I told her not to because that is so rude. Should I send him a message and say that he can't use my friends for that and should I tell the new girl the same thing also?