How do you know if someone rreally loves u?

Before giving an explicit answer people should know, There is a DIFFERENCE between LIKING someone and LOVING someone! There are "signs" that may give you a hint that there might be a connection between people, such as:

1) They are caring and attentive without the need of you asking them.

2) They are capable of listening to you blabber on about life and such for hours!

3) They don't mind not going out with friends if it means leaving the significant "other" alone.

4) plus it kind of depends on your age

*** Adding to that, don't confuse love for chemistry.

At times you'll find people that you feel an immediate connection 'chemistry' with (eg: a sexual attraction or so).

Only time will tell how much that person really loves you!

For this reason there are those who prefer to keep sexuality for after marriage, because it confuses a person, and is able to get even 2 incompatible people together for a while, until it wears off.