Aptitude has nice scenario resolvers.
It looks odd to someone not used to ncurses GUI and admittedly it's very special.
But when it comes to difficult problems where you need intelligence and details there's probably nothing better, besides the apt commandline tools and dpkg itself.
It's worth to learn the few main keys you need.
First of all have
F10 -> (right arrow)Help -> (arrow down)Help(Enter)
for a first clue. Read them all and remember those you need mainly, like
+ - _ q / and arrow keys, enter, and g. Ctrl+u=undo
After your choices are done, press g to see what would happen. Aptitude tries to resolve your requests, sometimes offering scenario alternatives.
You can move back from the 'g' screen (main scenario) screen with 'q', or accept and start download with another 'g'. 'q' is generally an important key ;)
Subscenarios have a small menu bar (next,previous,...) which works with arrow keys.
Note that although there's custom to cancel or close a window with Esc key (sometimes quickly twice), in aptitude you need to activate a button (like OK) with Tab, then hit Enter. Old GNU custom, or maybe Unix i don't know.
I say this because i know people who even couldn't finish the first installation because they simply didn't know ;)
Usually even hard cases can be solved by deinstalling some packages temporarily.
Often, upstream coders or maintainers upgrade to some requested library within days or weeks and the package becomes installable then. If that doesn't work for you you can tune your sources.list to include several alternatives, like testing/unstable/experimental. My experience is that i could trust apt (and aptitude) to great extend to manage this intelligent without even tweaking /etc/apt/conf.d.
If there's something looking really unresolvable, it can often still be done via dpkg --force.
Consider if you really need a package that hard that you risk to break something else, and if you can deal with occuring problems. Better ask this (or debian-user) list about it first.
hth