Zero peristalsis?

I have been constipated for 2 decades caused by the Multiple Sclerosis.  It is getting worse and now only way of working is aggressive laxatives.  I have had a colostomy which is not working now, battery implants to stimulate the sacral nerve have failed.  There is no peristalsis throughout my system so what is next please?  Can you help me because I really feel on my own here.