Hi Kelly,
I live by myself, so I've looked at a bunch of those "Cooking for One or Two" cookbooks, and I really wasn't impressed. Part of the problem is the "take one pork chop and half an apple" kind of instruction...just try to find pork chops packaged individually in your average supermarket, let alone half an apple.
If your mother likes to cook, I would just get her a good, easy cookbook with inspiring pictures (maybe Good Housekeeping) and a bunch of freezer bags and dishes, so she can make regular recipes and freeze the extras. That way she won't have to cook every day if she doesn't feel like it.
If she's not likely to cook for herself anyway, "now" gave you a bunch of other ideas. One other suggestion, depending on availability and budget, is a "personal chef," even if that person is actually a neighbor or culinary student. Also, if you can line up someone to assist with her grocery shopping, that would be a big bonus.
Good luck. I went through this with my mom, and I know it's harder when you live so far away.