How can someone differentiate between love and lust... help me

Wow, don't ask an easy one... lol

I think it might be an easier job if you gave us some context to the question, what's the situation/feelings involved.

Really, the short answer probably is, from my point of view, you can't not easily anyway and the two are probably not mutually exclusive.

I can love and lust after someone at the same time, but I love them even when they have done something to upset me, I don't always lust after them when they make me angry. (Im not sure that helps you, but it was my thoughts).