For having friends round, why not do a course each? Someone brings the starter, you do the main, and someone brings dessert? And do a pasta or rice main, or something which is cheap. Your friends aren't going to expect filet steak - I'm sure that they're more than happy to just have a night out.
Use the library rather than buying books.
Check Aldi and Lidl in advance to see what they have on special offer and plan meals around this.
Sell the car and clear the cc debt.
Other posters are right about having one nice meal per week. Myself and the other half try out a new recipe - again, you can get recipe books from the library.
Sign up to Groupon - you could buy someone a meal voucher as a birthday, wedding present (ensuring that they know the time limitation).
Well done on trying to get on top of your debt.