The song you love does not need to be the song you are best at performing.

Loving something and being good at it are separate matters. The piece that moves you may sit outside your range, your technique or your temperament, and the one you perform beautifully may leave you fairly cold, which is disappointing only if you insist that the two must line up. Both relationships are worth having.

Keep the thing you love as something you do for yourself, badly and often. Give the audience what you do well, and do not let anyone talk you out of the private version. A life with only your best material in it would be considerably poorer than one that also holds what you simply adore.