Where do I start I am over weight and want to get rid of it!?

I am 25 years old, 5'0 170lbs and 13 weeks post partum, however, I was 170 when I got pregnant with my little blessing. I just feel so ashamed of my body, I have become a little depressed about it. I am so ready to feel comfortable in a bathing suit. I also feel bad for my husband, I know it sounds crazy, but I am not the same girl he proposed to 6 years ago. He would never tell me, but I just know he has to wish I looked like I used to. I just want to look like I used to, and feel good about myself. I don't want to do atkins, or any other crazy diet b/c that never lasts. Any advice??