I had the same problems with not honoured page breaks and so I made each story a separate file. But after doing some trial and error with Calibre preferences and when studying the MR forums I found:
You can insert this line in your html file wherever you want a page break. If you use Calibre don't opt for:
'Do not split on page breaks' in 'EPUB Output'. I think similar preferences are in other programs too.
Your original file will be split into as many separate files during the conversion process as it has page breaks, so each chapter will be an individual file as it was recommended by DSpider. The original file will not be imported into your Epub. The Calibre viewer shows the text correctly with page breaks and I think this will work for any device because of the splitting of the file into many sub-files.