Why WON'T a guy say it's over?

i started seeing this guy about 5 months ago. in the beginning, he's was very attentive. calling/txting several times a day. some txts gave a red flag, but nothing to really worry about. he also made "future" remarks about us. then seeing him became less and less. although we still talked on the phone and txt'd. he "disappeared" 2 weeks ago, no word, no replies, nothing. so i txt his son and ask if his dad is ok. well, he [the guy i was seeing] txts back that he got my messeges. but he still won't say that things between us are over. i decided to say i was moving on but he still says nothing. like it doesn't matter i even worried he might be hurt. so why would a guy just go away? not say anything? if he wants it over.... just say so. but why won't he???