Can't figure it out

I have been trying to lose weight for a long time. My son is now almost 4. I am 5'3.5" and 131 pounds. I want to be at a comfortable 118-120. I can't seem to lose the last little bit. I eat a banana and have black coffee every morning. I eat 2 slices of turkey and an apple for lunch, and I usually have a fruit and lowfat yogurt smoothie and small roll for dinner. I do an hour of zumba everyday. Why can I not seem to lose?
This is me on New Years(on the right) with my twin sister who just had a baby 8 months ago.
^This is me on Christmas with my hubby. I have a baggy sweater on but this was all I could find.

Quite honestly, you look great. I know you probably don't believe it, but you do. How many calories are you taking in a day? It doesn't sound like enough. If you're not getting enough calories to sustain yourself, your metabolism will slow down to compensate and you won't lose anything.

I eat around 1200. I use myfitnesspal.

Quoting The Mrs White:" I eat around 1200. I use myfitnesspal."

Well, if it's any consolation, you look great. And you're very pretty, too.  

I am the same height and 135 is healthy weight for that height. 118-120 would not be healthy.

I think you look great! From the sounds of it though you aren't getting enough nutrients...that could make it harder to lose weight if you aren't eating properly.

You look awesome. I know it might be hard for you to believe that, but you do.

You look great! And you have awesome posture

I think you look great!! The weight you are aiming for sounds a bit low.

Thanks ladies. That helps a lot. I'll add a bit more in my diet. I overcame an eating disorder in 2007 so maybe it is stemming from that.

I agree with the other ladies. Thats not enough to fuel your body so it it storing what you eat. Try adding in more fruit and veggies to help you get good nutrients and not add in fats (even though fats are good in moderation). If you had a problem with an eating disorder in the past that may have something to do with you eating so little. So slowly add more in so you feel comfortable. try aiming for a minimum of 1200 calories a day. Hope this helps!