You can just feel it. I've never experienced true love, but I've crushed on a girl five times!! Everyone knows love once in their life. You know if it's true, though. All those sappy, silly love songs from the 80s make sense, you think about them all day long and nothing else, and most of all you want to spend every second with them. Personally, I'm in a situation right now myself. I seen some girl, but never met her face to face. My heart is telling me that I truly love her, but my mind says it's a crush. So even I don't know it all. But trust me on this. You know true love.