Well, you probably have known love before. It could have been towards a parent, grandparent, sibling.....etc.
Love is love....it is beyond me to define it for you. It also has different degrees......it is a growing thing, anything that grows can also die.....please remember that.
If you are having to ask others if you love someone, then you probably do not.
It is internal first.....then we show it externally.