9 months ago:
Do you feel hurt by staying in the band? Feel like you're not satisfied with what you're doing? Want to be the lead vocalist even if your best friend is currently taking that role?
Everything in excess hurts; selflessness included. If staying in the band is only doing you bad, then put your self-respect to shine and find a way to make yourself feel better, even if it means leaving the band.
Being altruistic is sometimes blindly encouraged but still a terrible way to live. The correct way is to be 'nice'. Being altruistic is caring for others at an high level and absolutely ignoring yourself, but being nice is caring for others at an high level but always after keeping your stuff in check first.
I don't want other people being happy at the expense of your own happiness. Stand up for yourself, man!