According to Osho, a negative mood develops alongside sensitivity because life moves in polarities: the capacity for joy, love and compassion inevitably grows with the capacity for sorrow, hate and anger. They are one energy—'lovehate'—two poles of the same current. Instead of suppressing the negative, let expanded love/compassion absorb and transfigure it, creating harmony rather than phoney positivity.
When you become more sensitive and open, you feel both happiness and hurt more because they’re two sides of one coin, so let your love hold the hurt instead of fighting it.