
There no reason to endless your trying to explore. Like threesomes, or wanting to break up. One day when someone brings it up asking then you say yeah I’m bi. If she wonders why you didn’t tell her. It’s I was with you. Being bi doesn’t change our relationship. I still wanted to be with you.
Just tell her man. If you don’t think it’s safe, don’t tell her. If she doesn’t accept you, she’s not the one. If she makes weird assumptions, be prepared to explain and correct. Make sure to tell her this isn’t you asking for an open relationship to experiment( unless it is, in which case you have to say so, very clearly)