@Wholesome_Goth , I think in your case it might be like @RandomBuzziness suggested, in that their friendship or romance levels might not have been high enough, since you did state that your Sim barely knew the Sims that invited them.
Also, did you check the inviting Sims's work schedule? 🤔 They could simply be leaving because they have to go to work.😉
In previous Sims games (TS1, TS2, and TS3), I used to buy the Prima Strategy Guides for the base game and each expansion, so I could better understand the mechanics of how the game worked. While the strategy guides were not 100 % correct, since a lot of their information was based on earlier models for the game or pack, a lot of what they had in them turned out to be correct. On one or more of TS1, TS2, or TS3, I thought I had read that Sims will leave if their needs are too low or they have to go to work, so it would make sense that this might be the case for TS4 as well. But it isn't a guarantee either. 🤨 (I also could be remembering wrong since those games were a long time ago, especially TS1 and TS2!). But it is times like this that I wish we still had those strategy guides for the game.😢 A lot of the info was not interesting to the average player (though much of it was), but I found these bits of info about the mechanics of the game to be interesting. 🤓😃
And yes, while I don't know if personality traits have anything to do with this behavior, it is possible, and I wouldn't trust an evil Sim either! 😮 😃 😉
