1-4 can be covered by getting her arse and yours down to stepchange or the CAB and talking about it.
No5, You could make her bankrupt or she could make herself bankrupt. She might lose her house and car (if it’s worth more than a couple of k) and she’ll not get credit again for at least 6 years. The council might re-home her or they might not (as she may be seen as making herself homeless,I don’t know). Guess who will be expected to put a roof over her head?
No 6 , WASH YOUR HANDS OF THE WHOLE THING! I suspect your wife is pressuring you to help out. Right? You need to convince her that it is BOTH your futures at stake here.
Whatever happens it will all be your fault anyway!