Well, it is still up to him what he wants to do if she dates. He needs to control him and his choices, not her. So, there are lots of possibilities, like:
W: Hey, is it OK if I date?
H: That is really your choice. If you date, then I will proceed with the D.
--nothing wrong with that if the person is really ready to D, but I don't think that your friend is...
H: That is really your choice. If you date, I won't like it but I will tolerate it as long as (some set of rules.)
--yuck, either accept the circumstances or don't, but don't go this route and live together while sulking and brimming with anger and resentment
H: That is really your choice. If you date, I will be fine with it as long as (some set of rules.)
--only do this if it can really be true
H: That is really your choice. If you date, then I won't be bothered in the slightest -- no rules required.
