Entering and exiting CAS or loading into a game removes Secret Lover relationship from replaces it with Partner/Dating/Boyfriend&Girlfriend status.
I first encountered this bug while playing with mods. So, I initially thought it was a mod problem. Specifically, EPO Mod 1: Family Preferences. I got the option to change my Sims' Preferences from "Not Wanting Kids" -> "Happy to have kids". When I clicked agree to the change, both of my Sims' Secret Lovers became Partners. I got the notification pop-up right after. They still have the sentiment but the "Secret Lovers" relationship tag is changed to Partners. You cannot ask to be Secret Lovers again without cheats/mods. It removes the interaction.
However, I encountered a similar issue with my married sims. I raised this concern in the this bug thread. With the married couple, after entering CAS (with cas.fulleditmode), made some adjustment to their traits, and returning to Live Mode, I got a pop-up that so-and-so became the girlfriend/partner of my sim. They just got married the day before. You have to re-enter CAS and manually set the relationship to Married to fix the bug.
I encountered the bug a THIRD time with Secretlovers again. This time, I entered CAS without cas.fulleditmode and without adjusting anything on my Sim (Simply entering and exiting), and my Secret Lovers (My Sim had two) were all changed to girlfriend. I got a pop-up (so-and-so became My Sim's partners etc.).
The issue is not limited to only CAS or Traits changing. It happens upon loading into a game too. I was testing WITHOUT mods and it did not take me long to re-encounter the bug.
First, I removed my mods and tested the game unmodded. As soon as I loaded into the game, this happened:
Then, I put my mods back in. Loaded the game up and the exact same sequence of circumstances happened. Secret Lover and Romanced Sim both became Partners.
The last relationship change is of note, since they just had a high romantic bar and I did not make them official/committed partners or secret lovers anymore. But the glitch set the relationship to "Partner" automatically.
Edit By Crinrict: Adjusted pack tag to fit conventions of the forum.
Not sure if it's the same thing, since I do not own the Royalty pack, but my married sims are also reverting to "partner" over and over. This happens with many different households, and I am not playing with any mods.
Interestingly, sims that were dating but then decided to just be friends are ALSO reverting to partners upon loading. This does not happen with sims that have broken up. Basically, all sims that were ever in a romantic relationship and don't have a negative romance bar become "partners", even if the romance bar is now at zero (the romance bar itself never changes in any cases).
I've been fixing them all manually so far, but it's been going on for a while and getting pretty annoying since I play rotationally and currently have over a dozen households I go through sometimes and every time I load in, or even sometimes when I don't, and am just in the middle of live mode, this happens.
For instance, most recently, I have a sim who completed the serial romantic aspiration, then became "just friends" with all but one of her partners, who she then married. Upon loading, she was back to being partners with all of them. So, I had her once again end all the the other relationships and then re-marry her spouse...only to find that as soon as the marriage completed, I was bombarded with notifications that she had simultaneously "become partners" with all her exes again. They weren't even on the same lot at the time lol.
So...yeah. Please fix this.
