let her have the kids for a couple weekends. explain the situation to work if they don't already know, and ask for a couple of Fridays off. grab a knapsack and fill it with a tarp, a thin quilt, waterproof matches, the minimal amount of food to sustain you, some whiskey, a knife, a couple band aids, a water bottle, then walk into the woods a day and a half turn around and walk back.
Monday back to the grind, spend a couple of your free hours during the week thinking about how you can lessen your load, be more waterproof, be faster, the further you can walk the better.
The second or third best thing I did in my entire Divorce Busting experience thus far.