Necessity of Meditating on Compassion

I have been practicing different kinds of meditation for a long time, mostly open meditation (somewhat like Vipassana). I recall that when I practiced compassion meditation, I experienced one of the worst periods of my life. Now, I began anew to practice a form of compassion in meditating on self-compassion, as I read about it. Yet, I wonder if this is not more unwholesome than not for me. 1) Is it possible for a person to be averse to compassion, or for whom compassion is a element of struggle and difficulty? 2) Is it perhaps easier for some people to meditate on emptiness or wisdom in order to indirectly generate compassion? Would such a possibility be less 'wholesome' than actual compassion meditation or even than compassionate acts? 3. Is it possible to forego compassion meditation completely and solely rely on compassionate action to develop this quality?