Is the pursuit of happiness a selfish motivation? There seems to be some admiration for someone who says "I don't pursue happiness." We quickly nominate them for martyrdom.
How about
being happy? Is it selfish to
be happy? Can you just be happy without pursuing it? I don't think so. All animals naturally pursue happiness. Even if it's just finding a sunny spot on the porch on a cold morning. Even if it's waking up with a hangover and going to mow an old ladies yard for her. Your motivation for doing that was to make you (and her) happy. If that makes you feel guilty... then maybe you should stay home and whip yourself on the back with one of those little purging whips until you bleed.
I don't see any way around it. Everything we do willingly... we do because we want to. Because it makes us happy or at least happier than we'd be if we didn't do it. The only way that I could say that "I don't pursue happiness" would be to enter into some kind of slavery wherein my free will was denied. Then I could say "I don't pursue happiness because I CAN'T pursue happiness".