Leaving my boyfriend

My boyfriend has gone on holiday for 17 days to America. I invited him over before he left because I haven't been happy lately and wanted to talk/split up. However when he arrived he was crying his eyes out so I didn't have the heart to do it (stupid, I know). Anyway I can't see him now for 17 days so would it be totally heartless of me to end it over text? I don't want to ruin his holiday but my reasoning is that I feel I can't trust him. Do you guys think I should wait til he's back? If I do then I'll have to act like everything is ok until then which surely is worse. I'm really stuck so please help!