ask him
A guy is sincere if he says the truth. And if he is honest.
There is no way to tell. A psychopathic killer can be very clever at sounding very loving and sincere, for example.
She doesnt have boobs or a vagina
if he is truly happy around his girlfriend and will do anything to be with her
either tell them that and be really nice and sincere about it, or you can do something special like take them to their favorite place or sing them your guy's song but make sure its sincere ( i hope this works for you ) (:
That's a good thing! This depends on the kind of guy he is. If he is a player and/or has had many gf's, take the I Love You with a grain of salt. If he is a nice and sincere guy, then tell him you love him back!! but only tell him if you really mean it.
Tell him if you Love him or not. if he's being sincere then he deserves a sincere answer.
you tell him how much he means to you. say hes important and hes your whole world. :) :)
When you feel that you truly do, you should let him know how you feel.
It is sort of obvious. If he truly loves you, he will tell you. If he does really nice things for you, he probably loves you.
I'm sure if it has been 3yrs and he is still interested that should tell you something - he is sincere.