Im confused, what should i do ?

kso, my so called boyfriend isnt giving me the time of day. we used to text like everydayy. but now we just barely talk. one day i texted him & asked him why we dont talk & he claims hes busyy. meanwhile on facebook my friend dayna wrote on his wall saying sorry i cant reply your text me phone is being retarded, /: it made me so confused, like is he cheating on me ? flirting with other girls ? i have no idea what to do. when i text him he doesnt reply.. & i asked him, if we were still dating & he said yeah. wellll whats on earth is going on ?! if were still dating why are you talking to other girls but me ?!