Digestion

I've had issues throughout my life with chronic constipation. The last few years, I have had many, many, uncomfortable bouts with "IBS"- I want to describe it as that- but the symptoms are pretty intense. My stomach- or lower bell/intestinal area I should say, swells out up to the point where I look like I'm in the third trimester of pregnancy. It is very uncomfortable, and sometimes so bad that I can't eat and often time feel like it is more difficult to breathe. A few years ago, this contributed to an eating disorder that happened suddenly (mostly bulemia), as I would be so hungry but my stomach would swell and I would be too uncomfortable and have no room for food in my stomach, or so it felt. I went through treatment for that issue and am now healthy. I have tried colon cleanses, which help initially, but the problem comes back. Am I allergic to certain foods? Is there some sort of parasite? Another issue? In order to use the bathroom and get relief from at least some of the gas/air/swelling I have to use an enema. That provides a significan't amount of relief, but doesn't get rid of every gas causing the problem.

I quite healthy- lots of fruit and veggies, not a whole lot of meat or fatty/sugary foods. I do crave salt all the time, and estimate I consume a lot more than the recommended amount. I also suffer from chronic back pain both in my lower back/sacrum, and my neck and shoulders. I often suffer from insomnia.

Any ideas? Thank you!