I'm new and need support, and will give back too

Hi there.
My name is Melanie. I'm 148 pounds, I'm 23 years old. I run almost every day, I ran over 6 miles last week alone. You would think I shouldn't have problems losing weight, but I do. I have hypothyroidism. If I control my calories to 1350 a day, I can maintain my weight. If I eat about 1900 (the suggested amount in my weight range to maintain weight) I actually gain. I only got artificial hormones a few days ago, and I hope soon all my efforts will pay off. I don't just want to lost the extra 30 pounds I gained before they found out what was wrong-I want to be healthy too.
Am I the only one on here who has hypothyroidism? is there anyone else out there with the same problem? Even if not, I don't want to gain more weight. I want to keep working out, I want to get healthy. I need support.
I moved to a new state 6 months ago too. I have no friends, and that means no support system. I also have 2 kids, ages 5 and 2. I attend college, and once my youngest is in school I plan to return to work as well. I have alot on my mind and alot to deal with. I guess I just need someone to reassure me every once in a while, tell me all this work isn't in vain.
Thanks everyone.

Hey, I know this is kind of major for "casual advice from a stranger", but have you ever looked into the paleo diet solution? I know the idea of a "new diet" probably doesn't impress you at this point, but its not really diet....its actually a totally different way of eating. I have several friends and loved ones who have gone to this option to help with the treatment of illness like diabetes, chronic fatigue, depression, and many others, with shocking results. I am so impressed by it that I feel it is worth looking into for almost anyone. It changes the way your body works with food, and if you actually follow the guidelines, its extremely hard to not loose weight, even with no exercise. I know I sound kind of infomertially, but I wouldn't bring it up if I didn't think it could help you!

Best of luck, and stay strong!