Is It Possible to Get a Diastasis After Tummy Tuck?

Had full tummy tuck 2003 now pain down the center of abdomen, especially around belly button. No pain prior-never pregnant. Tummy tuck due to 190lb weight loss. Pain sitting, walking, opening doors--anything that involves abdominal muscles. My abdomen distends, especially before BM. Only relief: wearing compression binder or laying on side. Been to PS many times-doesn't know what to do. CT scans show no hernia. Sent to gastroenterologist, general surgeon to have gallbladder removed (didn't), physical therapy, pain clinic. Have appointment with general surgeon-looking to see if anyone ideas what the problem could be-what could have caused it. Thanks.