What Do I Do with My Sim Self's Sister?

Like most of my relatives she is in the game to "complete" the family tree. I modelled my sim self's sister after my sister in real life along with her real life partner. For a while she lived in San Myshuno in my sim self's first home after he got married to his first wife.

Thanks to MCCC she has been married three times! Once to Orlando Penn who is Military Personnel in Strangerville, he moved in while her real life partner was still living in their house and this marriage was annulled. Some time after that MCCC married her off to Nasir Keene and this time the game showed her real life partner as still her boyfriend while married to Nasir and again that marriage was annulled and i moved Nasir out.

Not long after that, MCCC marries her to Nasir Keene AGAIN! and he is currently living with her and her real life partner. She also has two kids with her real life partner which were made with MCCC story progression.

I don't know what kind of life she is living here but i've never really got to play my sister and her boyfriend because MCCC keeps making these outrageous decisions.

Do i reset her relationship with her real life partner so they can be together and forget the marriage with Nasir or see what else MCCC sets her up for? Has anyone else experienced this behaviour with unplayed sims?