So point of all this? Timelines are important. Even if your SO doesn't want one, the day they are ready for one you should have a mental diary or written one of everything you've remembered.... 99.9% certain....
No longer together
"There are times when our reality is nothing but pain, and to escape that pain the mind must leave reality behind." Patrick Rothfuss
Timelines, confessions, open journals get out what you remember with the option to add more if you remember more. It is a balm to get out the ugly and the toxic.