I lost 30kgs prior to meeting DF and kept it off really well till I got pregnant.

I changed my diet, threw out the junk food so I couldnt be tempted, went for a 30-40 minute run each day (built it up as I grew fitter)

I must say though the biggest thing was- I got happy. As soon as I found ways to make myself happy, like making sure I got out of the house for even a short while each day etc, the weight just seemed to fall off (with help).

Alternately there are things liek Duromine which my partner is on, but htey have a low rate of keeping weight off as many people fall into old habits when they go off them.

What is your lifestyle and diet like?