What does i love u mean?

waht is the meaning of when a girl says i love u and when a guy says i love u what does thoes htign means when girl says i love u does she mean it and when guy says i love does he mean it is that realy ture or what i mean there are alot of thigns going on wiht a girl and guy somehow we dont trust each ohter and that is not good bec we are afreidn to get hurt or cheat on each ohter but one wil know til they find the rightr person but is that true is ther one girl and one guy out there who are true ? evry girl is counted for as guys too? is that realy true