How can i know if my girl love me truly ot not?

Time will tell: Time is the best predictor.

Why do you ask?: You cannot know another person's mind, even after you're together for many years. Ask yourself instead, "Are the two of us happy together? Do I have any reason to think that she will not want to be with me as a faithful partner long-term?" The ardors of romantic love ebb and flow, but liking one another and the small kindnesses between lovers should be there to sustain the relationship.