Welcome to MR dougfetch2!
Formatting poetry properly is one of the more difficult, if not impossible, challenges in a reflowable format such as ePub. There
should be easy css properties to do what you want, but apparently the demand isn't high enough for the IDPF (the ePub standards people) to require them.
There are multiple threads on here that discuss formatting poetry, but the basic answer is for the author to accept that some of the more esoteric shapes/designs cannot be done in reflowable ePub. If it is essential to have a specific shape, then sometimes inserting an image of the poem is the easiest option. The other option (not for the novice or faint of heart) is to do a fixed format ePub.
For your specific question of line breaks and justified alignment: I can only recommend <br /> and text-align:justify and perhaps setting a <div> with a specific width (and perhaps a monospace/fixed-width font). The page-break-inside, orphans, and widows settings
MIGHT help prevent breaking over a page, but it sounds like iBooks has a bug - what a shock...
Code:
CSS
div.poem {width:410px; margin:2em; page-break-inside:avoid}
div.poem p {font-size:.8em; text-indent:0; text-align:justify; orphans:0; widows:0}
<div class="poem">
<p>
Bacon ipsum dolor amet andouille<br />
meatloaf rump meatball, shank ribeye<br />
jowl turkey swine. Drumstick tri-tip<br />
brisket, cupim tongue andouille chuck<br />
spare ribs. Bresaola cow drumstick,<br />
tail boudin ground round sausage<br />
kielbasa prosciutto turkey andouille<br />
jowl spare ribs. Short ribs brisket.
</p>
</div>
The div width could be set to a value that just covers the longest line???
Sorry I don't have more help for you - hopefully one of our poetry formatting gurus has some better advice!
Cheers