Of course we do.
Sometimes we love the drink more than the person we are with ... sometimes we love the person we are with , with all we have but in our own selfishness we focus on ourselves and own desires.
Seeing/feeling/knowing you are loved is often an issue with the person who is not feeling it as well. Our idea's of what love is and how it is expressed is taught to use through various forms of society.
Sometimes tough love sure as hell doesn't feel like love to the person getting kicked out for their own good.
Also in a recent case with me. It didn't matter how much I did/said/showed love through my eyes. It was perceived that I didn't love them enough or as much because it wasn't " their idea " of how love should be expressed.
The 5 languages of love is a decent read and Dr. Phil's "Relationship Rescue" has some good examples of how the myths and expectations cause alot of pain and hardships in relationships where it's just miscommunication and misunderstanding.