I want to support my [erstwhile lesbian] girlfriend, but I draw a hard line at cis men...

Q:

How do I support my partner through an identity change that I am not enthusiastic about? My partner is starting to explore her sexuality more. At first, we both identified as lesbians. I know bisexual women and lesbians have a lot in common, but there are some things that we do not. I like sharing that part of my identity with my partner. If she settles on being attracted to men as well, we will lose that aspect of our connection. Further, I don't have any IRL lesbian friends so I would lose this connection overall in my life. Something else complicating this is that we are poly. I categorically do not want to have a cis man as a meta. That i...