I think that the only way that you will really know if someone loves you or not is when you get into a difficult situation whether it be financial or emotional.
If the person that you are unsure whether or not they love you will show their true self.

You will know that if the person in question stands by you and offers you support and understanding during such times, or only pretends to love you when things are good.

True love is when a couple truelly feel for each other and understand each others likes and dislikes,respects the others opinion on any subject regardless whether or not you agree.And just basicly be there for each other to share lifes experiences both good and bad without reservations or barriers.