Resolution Motivation... is it just by chance?

Someone once told me that if you tell your New Year's Resolutions that they are more likely to not come true. The logic behind this is if you tell the resolution to someone, you are already satisfying that part of you that does something with the desire to receive praise for it, and therefore have less to strive for in actually fulfilling the resolution. Does that make sense or did I just butcher it?  Anyway, I've already failed my new years resolution, but that doesn't mean i'm not going to keep at it eventually. Currently though, I have lost my motivation for it. Anyone have any advice for how to get motivation back?