I know exactly how you feel. Dont give up. Perhaps going to see your doctor for some help/advise might be an idea. There is nothing like going to be weighed by the nurse on a regular basis to give you the motivation to stick with it. Even taking your baby out for a walk is exercise, and the calories all add up. Its better to do a little every day rather than try and do an hour workout. You wont stick with the hour workout but just try to do 5 or 10 mins here and there. I know it seems like an impossible task but you can do it and you will get there.
I have got to lose half my body weight for medical reasons, I joined last week and have been sticking to my calorie limit, cant do much excersie at the moment due to joint pain. I weighed myself this morning and I lost 1lb. Bit disapointing, but its 1lb in the RIGHT direction!
Stick with it. By finding this website you have proved to yourself that you want to do something about your weight. Its the first step on the road.