SJ,
One suggestion that no one seems to have mentioned yet, so I'll throw it out there. Several airlines have affiliated credit cards that have large miles bonus offers for opening the card. I regularly get offers from both United and Delta for cards that have the fees waived for the first year, plust anywhere from 20-50k in mileage bonuses. Depending on the ages of your kids (some mileage programs may not allow kids to travel unaccompanied, but a 12 year old is sometimes considered an "adult" who can be the companion for a younger child), you might be able to greatly reduce your expenses for your kids visits by getting one of these cards and using the bonus miles to book one or maybe both of the tickets. Since you probably know the school calendar well in advance, you could book these well in advance to ensure you have seats.
If you are committed to working from a budget and not living beyond your means, you could also use one of these cards for as many of your regular expenses as possible (gas, groceries, food, phones, utilities, etc) in order to accumulate additional miles that could be used toward the kids tickets. Obviously very important that you track your spending and ensure that you pay off the bill in full every month. But if you are disciplined and careful then this is another way to use your spending in one area to bring down spending in another over time.
Regarding your livestock business, if you don't already you should determine some baselines for how much you are going to invest and when you will cut your losses if you fail to make it profitable.
Being in a rural area makes it difficult, but since picking up a regular second job is not feasible given your work situation you might also think about other possible part-time sidelines that might help bring in extra income that are more flexible, so that if/when you don't have paid work for your client you have something else to do that can at least bring in a little extra. garage sale/thrift store combing for items that you can become an expert in appraising and then sell on ebay or craigslist might be an option -- I'm thinking things like farm equipment, furniture, antiques, out of print books, etc. Difficult in a rural area, but might be a useful niche to explore.
Finally, assume you have already looked at whether or not there are generic versions of your meds that would be cheaper, but if not definitely do that. And do some research about when the patents for your meds will run out, if there are currently no generics. It would be wise to switch to the generic as soon as possible after it becomes available, as it appears your meds are very expensive. If they are related to any chronic condition that can be addressed by changes in diet and exercise (e.g. high blood pressure, cholesteral, diabetes (maybe not severe cases, but if early you might be able to turn things around)), then some time spent on researching effects of diet on such conditions and doing some experimentation with changing yours might be well spent, and might also help to bring the grocery bill down.
Personally I would not have cashed in the 401k -- I think you will find at tax time that the hit is much larger than you anticipated. I hope you are saving up for your taxes in the event that happens. But glad you feel good about your choice and are moving forward. Hope you keep coming back here in spite of the tough love you got. MMM and the crew really only want you to turn this around so that you can live a life not ruled by debt.