Is this just recent? Maybe it's a slump or midlife crisis thing? But regardless it's not right of him to try and push an open relationship on u esp if u have been manogomeous for 12yrs! Idk. Have u tried to bring up couples counseling? If he's having a desire for flavor he is expressing as other women (which IMO is def crass toward u), but he could be boarishly confusing his need to spice things up w/ talking about other types of women instead of relizing that he just wants some fantasy which u could probably satisfy if u r comfortable w/ some role playing. If it not any of these things or he does,want some fantasies that you can't or r not comfortable with n if he's not willing to talk about it in or out of counseling...then he maybe has decided he doesn't want to be in this relationship anymore. Anyway u slice it...even if he is hinting at ending things.. He has no right to talk to u n treat u like that! 12yrs!! I think you have earned a bit more RESPECT! But Idk ur relationship, so I can't honestly say where all that is coming from. Try to talk it out first, I guess.