I’m so sorry. I know it is hard. With little ones, I would use social stories to explain your point of view and what the “rules” are for family interaction. They just don’t know. Figure out what they are seeking from you and how that need can be met some other way. They may need to learn to play independently. Some OTs are really helpful with this kind of thing. Sometimes on you can hire a middle school kid to come over and play with the littler kids, while you are at home.
Set up a schedule so they know when you are able to focus on them and when they have to entertain themselves, and make a list of choices of things they can be doing on their own for them to pick from.
And forgive yourself. Can you think of a preferred activity or toy that you only pull out for independent play on occasion, and put away right after?
And acknowledge their feelings, explain what they need to do, and tell them for how long. “I can guess that you are feeling maybe lonely and not sure what to do right now, since our schedule has been changed for today. We had lunch already, and I need thirty minutes to do some things alone. You can watch this show by yourself, build with Legos, or play with X. After that, we will read two stories and then go outside to clean the snow off the cars.”
Their anxiety builds when their routine is changed unexpectedly and they don’t know what the day holds, and they come to you for reassurance, but they can’t articulate their feelings. Name the feelings and make a plan. This is why special education classrooms have such clear routines and schedules.