I'm aware this is an old thread and old news but I just wanted to add my perspective as I feel OP got a little bit of unnecessary flack.
I have a DSS and he didn't stay in my house for 12 months during covid - our households didn't mix whatsoever and my husband was happy, and even reassured, by this arrangement.
I am high risk and his mother was on social media attending various house parties mixing with allkinds right in the thick of the initial wave. We didn't want to take the risk.
My kids didn't go to school, nobody was allowed in our house, we work from home, washed our shopping etc etc.
Was advised by the clinical director of the hospital not to mix for a long time and we listened.
Each to their own but the fear of your health is something that's very difficult and everyone has to do what they see fit. I have two young children and wasn't willing to put them through having their mum sick again because of DSS's mother's bad choices. Call that selfish or call me Cruella, that's fine, but everyone's story is different and it's not always cut and dried.
We remained in contact with DSS, facetime etc and monitored the cases etc. When they dipped my husband would visit him outside with a mask on. He understood why this was all happening. As soon as we were fully vaccinated he came back.