I am attempting to utilize XSL to format results pulled from a document library, but unfortunately this is my first stab at XSL ever. The columns in the document library are fairly standard - Title, Description - but also contain a custom column which contains a lookup to another list and it can contain multiple values (separated by semi-colons):
DOCUMENT LIBRARY
Image:
The "Role" column is something I would like to use to 'group' the results. Problem is, I am not sure how to query the document library in a fashion that if a document is part of multiple roles, then that document should appear under that 'heading'.
An example output I wish to attain:

Is this possible using XSL? If so, what method would you recommend? I can educate myself if I know what to search for :) So if anyone knows of some keywords I should be googling for, please let me know!
Thanks