Soulness, from what I understand from your earlier replies, I believe that you are just not happy that your "love interest" has been snatched from you. But do think about it again, were you running in contention in the first place (were you actively chasing her)?
I guess your current intention to confess your feelings to her at this point of time (she's happily attached) is to hope that she would reject your interest and you can convince yourself that you should give up dreaming of becoming her bf. Like what others had advised, it would be a burden for her no matter she had feelings for you or not. Please think over your decision carefully, your "answer" would result in an unnecessary burden for her. The least you could do is to tell her when she's single (if you think it's worth being on the waiting list again).
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Sidetrack abit, I recently told a former classmate back in sec sch (late 1990s) that i actually liked her in the past and confessed that i did not had the courage to tell her. Btw,she is single now but she's already overseas (a foreigner), by telling her, I do not expect anything to happen but just to let her know that i find her really special in the past and was glad that our paths met once in a lifetime. I hope that will make her day as she knows that there is at least someone in this world who finds her adoring and for me, I managed to let go of my "emotional baggage". Btw, I'm happily attached to my gf now. No regrets but without any dire consequences.
