Dont bother - speaking from personal experience. While its a noble gesture it's a complete waste of time and wont solve any of your issues. Better to start preparing for separation followed by divorce.
Every case is different. Neither your experience (not mine which sounds similar to yours) can necessarily be generalised to inform what another arbitrary couple should do. If @Cruzer123 thinks that the situation can be salvaged and it's worth their while trying then that's their prerogative and best of luck to them.