[KEMINOKANA]

No it is not a good reason. You should have objected to the idea before he committed himself. Otherwise right now, the moral and culturally acceptable thing is for him to gracefully host the guests.

I think you are being jealous and selfish. U dont trust him either. Just coz ur dating does not give u the right to command how he should spend his free time. This is where dating couples go wrong. Dating only gives u privileges, not rights. Marriage gives u the full privileges and rights...and even then, common sense should always apply.

On a side note, I learned this the hard way. Exs are NO NOs. It is over, it is OVER!