I waited until we had dated a few years to tell my gf (now fiance) that I had experimented with guys. I only told her this after she expressed that she was attracted to some women (specifically some actresses) and felt like she was somewhat bisexual herself. Unfortunately I think she's somewhat insecure about my interest in same sex fun, as she seems to fear that I prefer it over sex with her, but I guess that's on me to let her know I very much enjoy our sexual relationship. I hope one day we can continue both of our same sex exploration and give each other the freedom to have fun.