Just like a man's BOB, you just need to go light.
Food
water, or a way to get water fast (Ie, filter and some water containers)
sleeping arrangements
change of clothes, warm clothes, way to stay dry (milspec poncho would be a good choice, and doubles as an improvised shelter)
Basic essential tolietries (include femine hyg.)
- Food. You don't need much. 1 MRE a day is enough, supplement with snacks like granola bars. A complete MRE averages around 2500 calories, by the way.
- Water. Keep some in the bag, rotate yearly, and get a compact filter.
- Clothing. Really all you need is some dry socks, preferably some good hiking socks made from something other-than-cotton, some longjohns (Again, cotton kills), gloves, hat, headwear (balaclava or beanie).
- Sleep. A bag rated for the conditions you'll face, usually a 15* bag will cut it. A milspec poncho can be used as a poncho and as an improvised shelter. Get the liner, too.
- Tolietries. Duh. Brush your teeth, take some baby wipes to clean up, and any female neccessities.
From there, add to it as you see fit. Ways to make fire, ways to defend yourself, things that facilitate travel (like flashlights), tools (multitool, duct-tape) and so forth.
Also, if you've got some hiking boots, keep them with the kit. If not, go buy a pair (check clearance sales, etc), and get a pair. Break them in, then keep them with your kit.
Since you're going to go with a car kit, with the option of travelling on foot, you should have two kits. One grab-and-go with the essentials, and one with a little bit more that you can abandon in the car if need be.
If you can, have a firearm for defense. Remember, you might be walking for days with it, through checkpoints and with other refugees. Hide it in your vehicle if you feel comfortable doing so. If not, at least have a pepper spray, baton, and a large knife (Kbar, etc) in your kit.
You should also carry some vehicular essentials in your car. Jumper cables, empty 1 gallon gas can, oil, antifreeze, and fuses, hose, and duct-tape. Learn how to do some vehicle-repairs your self, or at least know where things like the oil and antifreeze go, as well as how to change a flat (vehiclular ignorance is
not confined to women).
Cheers,