Doing whatever feels good is different from whether you fall in love with someone or not. In fact, a lot of people might tell you that, and not entirely cynically, that love is your ability to feel pain ... since everything ultimately comes to an end anyway. So I could argue that falling in love with someone can represent the opposite of "doing whatever feels good".
The former is hedonism. That's different than, say, developing a productive relationship with someone you might develop more romantic feelings for -- and yet being able to draw boundaries so that those romantic feelings don't cross over into other behaviors that might damage others.