I'm sorry you have to go through this, but there is no reason you cannot have a relationship after this surgery. It is hard to say exactly what your recovery will be because it depends on the method of repair that you and your surgeon decide is best, but I found a page from Mayo Clinic that explains the different approaches very clearly: http://www.mayoclinic.com/health/rectal-prolapse-surgery/MY00312/DSECTION=what%2Dyou%2Dcan%2Dexpect.
You can most certainly have a relationship. I want you to know that even if the surgery had complications for some reason, that would not prevent you from having a relationship. People have all sorts of medical issues, especially as we age. Women with colostomy bags can still have relationships, including sex. So I know you can, too.
If we can help you further, please let us know. Thank you for writing, and good luck to you.