for me it's Coldplay's "The hardest part"
Not that it's a girl infused song but because the line that states "the hardest part is letting go not taking part" to me speaks about giving up what you love. In this instance the inner turmoil we may feel about our cross dressing and who we are becomes calmed when we come out and accept ourselves by actively 'taking part' . When we deprive ourselves or are prevented from doing what we love the realisation that ' letting go' is actually much harder than accepting ourselves.
This has been my experience anyway. This song has had me sobbing my heart out, I'm not ashamed to admit.
I should add that the whole song resonates with me, have a listen to it and you may know what I mean.
Luv
Amanda