Doe he reli lyk me or is he jus using me ? im reli confused?

i met dis boi in october and we got reli close at da begging of the year, at one point we was reli close and seen each other every dai and wen we wasnt togeva we wuld b on da fne. but latly hes been chattin to dis gurl on da fne alot, she is reli obsessed wiv him, hes tryed tellin her to leave him alone but she jus wnt. he told me about, but he sed he cnt b bothered to try get rid of her, hes jus gna use her for her money, n shes 21 and hes 17 he lied to her wen he first met her and told her a diffrent age. he speaks to her all da tym and meets up nw. im reli worried him and her myt do somthink behind my bak. i reli lyk him, i fink i myt even be in love but i wana no if he loves me bak ? help plz