God knows I have tried to motivate my family to live healthier, and most of the time I just feel alone and like I am rowing a FULL lifeboat all by myself.
I think Almeeker's ideas are awesome (her ideas usually are), so I will add a little bit more here, not for exercise but for food.
1. We purchased an Alhambra water dispenser and water service, which has amazingly motivated everyone to drink more water.
2. Low cal cookbooks for busy moms are AWESOME. They show fast, inexpensive receipes that are relatively healthy, which might keep them out of the fast food lane.
3. Due my healthy eating, my friends and family know that I will NOT go off of my eating plan. Not for Christmas, birthdays, Thanksgiving, Mother's Day, Arbor Day, Groundhog Day or any other "special occasion." The great thing that's happened is that if other people host, their cooking is so much more healthful. If I host, people come over EXCITED about a delicious, homecooked and healthful meal.
Could you do the same for your special occasions? Host her family, and have an organic, lean meal with lots of veggies, etc? I understand that you live several hours away, so just make sure to make a big impact when you do get together. Also talk about your struggles! It may make her feel more human.
Oh, and one last idea - as Grandpa, you may feel compelled to always have treats in your fridge or pockets for your grandbaby. Keep fresh fruits and veggies for the baby. Get a sippy cup and instead of juice, put a little crystal light in it. My 1 year old son LOVES it, it keeps him hydrated with zero calories and no sugar. Give her PB&J on 100% whole grain bread.
We have 1 rule regarding meals (no matter who's house): you NEVER have to clean your plate, but you are required to finish your veggies. So, my 7 year old has learned to eat them first. We've taught her "priority eating." Where she will eat the protein and veggies first and leave the "filler" (carbs) for last.
Good luck, but I think your best bet will be to lead by example, don't pressure but be honest and open.
I don't have to lose 83 pounds... I have to lose 10 pounds 8.3 times.
Starting Weight: 307.................Starting Weight: 430
Current Weight: 233..................Total Lost: 197
Goal Weight: 150.......................Weight to go: 83
Weeks at FitDay (returning): 1