Intercostal muscle pain related to my ED?

I'm not sure which forum to post this question in, but since my pain is directly related to my weight, I figured this would be the best forum

I've been struggling with Anorexia and Bulimia for almost 11 years now. I have noticed that when I go through a phase of severe restriction and my weight gets below a specific point, I get unbearable pains in between my ribs (the intercostal muscles). It feels as if they have been bruised, and if I breathe in deeply I feel like my floating ribs 'pop'. I don't really know how else to describe it, other than it's very uncomfortable. I have been to three Doctors, had Xrays, and a massage therapist. I have yet to get any answers, I just know that it only occurs once my weight dips, and unless I go back up in weight, the pain persists pretty much all day.

Has anyone else experienced this and received answers and possible remedies (besides the obvious of weight gain).