By being honest with them about something that is an undeniable part of you? No person can ruin another free persons life unless the other person allows them that power. Our experience with any matter, a great session of lovemaking or having just been fired is always subject to our interpretation and what we decide to do with it. One person can experience that event in a completely different way than another. Everything is always about any individuals personal experience with the event, nothing else. At the most fundamental level that is what is always happening.
Life is difficult at best many times, and we each decide our path. If your partner is truly committed to the relationship with you, there should be an expectation of hope when coming out. If the SO just clean rejects it completely and/or wants to just walk away I seriously question the health of that relationship previously.
Oh, and FWIW, I suspect the original poster had mal intent from the beginning with the tone of the comment. I think it should have been deleted by admin, as it just seems inflamatory from the get go to me. I believe that is evidenced from the replies from a good number of thinking people here. Poster wasnt really looking for respectful back and forth or info. Just a degrading off hand series of comments