@Roberta,
For the standing up problem, do you have enough upper body strength to pull yourself up out of a chair with some kind of device designed for that, or is it more like BBB's problem where you need more of a boost from the seat to get out of the chair?
I've been looking at something like these devices to help BBB.
I don't think this one would work for her because of her torn rotator cup problems.
It might work for you when you are in your office chair working. You can keep it out of the way and just pull it over to you when you need it.
This would be better for BBB, but I'm concerned about how easily it could slide off a wooden or fabric chair while she's attempting to stand up. There is no mention of that in the catalog description.
Would something like this work on your office chair?
I think the best arrangement for BBB would be both of them, the boost from the bottom and the balance aid from the grab bars.