For me, crushes tend to have more of a physical aspect, or attraction. Crushes are more difficult (for me anyway) when there's not a lot of physical contact. Example: I have a crush on a certain Merriam-Webster associate editor because I can see the face and hair clearly, plus there's also the sound of the voice. I still cling to the term "crush" though because I have never actually met this associate editor in person.

This link may clear up some confusion: http://www.merriam-webster.com/video/index.htm