Morning sukaren
Would it be possible to time your visits before a mealtime so that you stay for however long you wish, then take her in to the meal - or ask a member of staff to come and collect her (then it's almost as if she's leaving you) - and just disappear - or if she will accept this, a quick see you (whenever you will visit next).
Sometimes I've said I'm popping out to the shops and 'Is there anything I can get you?' - which implies I'll be back but leaves it open as to when.
I did try the 'going to the loo' bit but apparently dad actually remembered and came looking for me - wasn't a problem as he sat in the lounge and had a slice of toast and a chat with the staff.
When he had a bad few days I did stay to put him to bed and did his usual bedtime routine, which he seemed to accept - but I'm not willing to do that all the time.
I found any excuse for him not to come to the door with me - 'no, you stay in your chair, you look so comfortable' or 'you watch your favourite programme, it's on now' or whatever will suit the moment.
Don't put on coats and such in her view, maybe leave them in the car or an office.
'Fraid it's not an exact science.
As for the phone calls - you know the staff will call you for anything significant, so ignore the calls until you want to answer (you may not want to at all). You know she is safe, so the calls are not 'necessary'. Does she call other people, (and if she does, is she pleasant to them)? Because her phone could suffer an 'accident' and need to be repaired - and never replaced. If you do answer, start with 'oh mum, so sorry, only got a (2,3 ...) minute, must pick up (name)/just off to do the shopping/cake will burn etc'
Sorry to sound mean - it's a case of self-preservation. You know you've visited, so you know she's fine really.
