A month? That’s not very long at all for a cat to get comfortable with you. I recommend getting plug-in Feliway to calm their neurotic behaviour.
Definitely not all cats behave this way. I know one who looks like a Maine Coon but acts like a Ragdoll who *cannot* tolerate being left alone by humans for more than a day. And when a human is in the room, needs a lap to lie on to feel content — will follow you until you sit down and immediately jump onto your lap. If introduced to a new human (in the presence of known humans, in their territory) will take about half an hour to decide to jump onto their lap.
Have you tried sitting quietly in the same room as them, posting on Piggington or reading a book? A consistent habit of quiet presence can make a big difference to them.
Are the two cats female? I’ve often found males to be friendlier to humans (maybe because they’re bigger?)
I once had a female cat whose favorite habit was pouncing on my toes when I was asleep and swiping at the backs of my knees as I walked. But I moved a lot back then, so maybe that was part of what caused her behaviour.
