Hi there! I'm in my late 20's, am a SAH mom, and I don't go to WW meetings either.
For me, planning is the key. I just sit down in the morning, or even night before, so that I have a plan to stay within my points.
I also check out the threads on 3FC to see what others are eating - this gives me lots of ideas to try. I browse "healthy" recipe sites to see what I can make. I do lots of wraps, pitas, and soups for lunch - with a set of twins at home, I have to eat as fast as I can!
As for motivations, pull out pictures of your "before" self. Or look at the clothes you used to wear. Pictures usually do it for me! I also watch a show on BBC America called "You are What you Eat". This dietician comes in and piles up the food that these people eat in a week and it is DISGUSTING! I always remember that I used to eat that way and my table now would look much better than when I started in July!
I am close to that 50 lb loss mark as well, and it seems like it is taking forever to get to! Some days I'm frustrated, and I go off plan, but I try to remember that I am changing my eating habits, not just losing weight.
Good luck with getting motivated and sticking to plan! Sometimes, we all just have off weeks!