What helped you get back to your pre-pregnancy or goal weight post partum?

I am getting so frustrated. The majority of the weight came off on its own pretty quickly. But I am still up 7 lbs from my pre-pregnancy weight and on shrimpy me that means a full clothing size. I started going to the gym 3x a week and while I can tell my muscles are getting more defined the weight still isn't coming off and my clothes are still tight. I already eat extremely healthy, but I guess I need to cut my portions even further.

I'm no stranger to dieting, I lost 30 lbs on my own before DH and I got together, but I eat the same way now that I did pre-pregnancy so I'm just wondering how much more I need to change my diet! Ugh..

I'm in a wedding in March and I'm hoping I can reach my goal by then..