Romantic Relationships decay/become negative fast with no interaction

Whenever my sims are in a romantic relationship, their romance bar is immediately depleted or starts to drain whenever they are talking. I keep getting pop ups that they're going to divorce each other even though their bar was just full. This includes a sim couple that just got married and said that they were extremely satisfied with their relationship, but then I check and the romance bar is empty again. I keep having to try and regain it over and over, only for it to disappear again the same day. This is making it very hard to play my game and very frustrating.