Partnered Sims turn into siblings

I have large family, about 100 sims in total. They all have one ancestor, about 20 generations past by now. Many of them married each other and had children. Key pleasure from the game for me is to develop a dynasty, generation by generation.

After recent update many of my married couples were destroyed and treated as relatives: they still married, but have no romantic actions at all. Moreover, family tree disappeared as well: it was broken, shows marriages between adults and a children, etc (nothing common with reality). I cannot find couples for my sims anymore.

Moreover, for some sims (ex-couples, that are not treated as relatives after update), the marriages were disappeared with no possibility to make romantic actions (only massage available).

It looks like I cannot continue to develop my gameplay as most part of my sims started to be relatives along with other bugs with sims' relationships. No more value in playing, feeling disappointed.

Cant wait for the next update with these bugs being fixed.