He is cheating and i know it!?

i used to be friends with this girl jessica in 7th grade now were in 9th grade we aren't friends anymore but i liked this dude and i was like on myspace and my name was i love roberto and so my old friend jess says mimi u got a boyfriend named roberto to! and i was like yeah she asked me what he looked like and she was like hmm i showed her a picture and she said that's my man! i was like ok whatever so i know he is cheating but i really love him please help me what should i do!??