Yes, that's right. ACR 2 (still in beta) has three features: autonomous engagement, autonomous marriage and autonomous breakup. I think it fits the bill when it comes to doing what you hope your Sims will do autonomously.
You can download ACR 2 from
Simbology and give it a shot to see if any of those autonomous features are what you're looking for. The setup is neither easy or difficult to do. Read the documentation that comes with the mod for full usage and if there's any issue using ACR 2, post them there.