from your description it sounds like you have a hernia (I can't say for sure without examining you, but it sounds quite likely). This involves a weakness in the abdominal wall, where bowel can sometimes protrude through, especially with increased pressure (which is why it bulges out when you increase your intraabdominal pressure when doing a sit-up like motion).
To have this fixed requires surgery, which may not be an option for you in the near future because of your insurance situation. In the meantime, if you are unable to get it dealt with, you need to be aware that rarely the bowel can get stuck (strangulated) outside the wall. If this happens, the oxygen supply can be cut off to the bowel, and this is very serious and requires immediate surgery. If that were to happen, you would have significant pain and the bulge would stay out- so if this happens, make sure to have it seen right away. This is quite rare, but something you need to be aware of.
I know that it is difficult, especially after children, but getting your weight into a healthy range should be a priority right now, for your health, your self esteem, and for your kids. Every little bit makes a difference, so try starting with somethig manageable like 5 or 10 pounds, and go from there.
Best of luck,
Thank you very much for your prompt response. I have begun playing on a softball team to try to lose weight. So far I've already lost 20 pounds! Also I joined a gym that opens in November (Planet Fitness). I am excited and I can't wait for it to open. Finally I found a gym I can afford! It is only $10 a month!