TMJ can be one of those annoying little problems that 50% of the population will get a some time or another during their life. Pain can range of mild and annoying or painful and debilitating, but lucky their are many treatments. The key is to find what initially caused the pain. You've been doing some reading so I'm sure you've probably read about jaw clenching or teeth grinding or maybe even jaw misalignment. Though the previous listings are things you'll worry about if you don't get this pain cleared up in the next few months.
In short, you've aggravated a joint, and just like a knee from running or an elbow from tennis anything that is aggravated becomes inflammed. The inflammation is what gives a cramping with fullness sensation and makes you not want to use that particular joint all that much. Most TMJ experiences will end in about 3 months with appropriate therapy...so what is the appropriate therapy?
Number one you'll want to make sure that you load up on some anti-inflammatories and my favorite is Ibuprofen (Motrin) and usually a high dose like 800 mg bid, 2x a day. You can take ibuprofen tid, 3x a day, but you don't really want to go in excess of 3200mg qd, per day. That will help with the inflammation, but you then need to concern yourself with the rest. Make sure that for the next 3 months you have her eat some soft foods. Give that joint some time to recooperate as you would any other joint.
If the pain persists for more than three months then you'll want to see a dentist and have the initial things that I listed checked out. However, with the history that you gave I believe the regimen that I listed will take care of her.

Hope this helps a little bit and I hope she feels better.
PS: Don't take the vodka with the ibuprofen.

The alcohol numbs the pain, the medicine will relieve it.