Hyphen in English

I would like to know how to write these words:


Un-break my Heart (used by Toni Braxton) or
Unbreak my Heart

The Power of Good-bye (used by Madonna) or
The Power of Goodbye


How to write these words?


un-break, good-by, to-morrow, no-one?

I've seen all these forms so I'm puzzled.
Thanks a lot.

Unbreak Goodbye Tomorrow Noone. Now feel my bemaddened heartfelt wrath. You unbecoming dick-head.

"Goodbye" and "tomorrow" used to be hyphenated but aren't any longer. You'll often find the hyphenated forms in older books dating back to the 1940s and beyond.

"Un-break" is a made up word, and since the song's writer(s) used a hyphen, then I would suggest using the hyphenated form. But what does it matter?