You might try Feliway, a "feel-good" hormone that reduces anxiety in cats.

I wish you the best.

The move is the obvious trigger. I suggest you get your son to wear a t shirt to bed every night for a week and send it hoome to Bonnie, she may be missing him and is grieving over his being gone. I might also suggest placing a cat bed into the new office so she can hang out in there...preferrably in a place close to where she would have hung out if your sons bed were in there.
I also suggest you get some literature on the Tellington touch method, which might help mellow her out. Good luck

Excellent suggestions from mazer.
Just would like to add to stay away from steroid shots. Bad for a cat and they do NOT solve anything. Just a temporary fix, as you've found out.

Fish oil is an excellent supplement for a healthy coat. Just get some Omega-3. (I use Omega-3 Pet from Nordic Naturals). I use half a capsule (that is 500mg) a day. Not all cats like it, so start with 1-2 drops on food at a time so that Bonnie can get used to the new smell/taste, then increase to 1/2 capsule.

Cats can be allergic to many things (fish, corn, gluten, yeast, preservatives, chicken, etc...), and it takes a while for their system to react. So, examine her diet carefully.

I've been fighting alopecia in one of my cats (belly--area of her spay) since I adopted her (no parasites). Vets think it is food allergy, but she simply won't touch the alternative foods. We tried SO MANY things (including Feliway, Convenia, animax, hydrocortisone...), but after 4 weeks on 500mg of Omega-3, I am starting to see some results. Not yet there! And of course she is not going to get any vaccination until this is solved, or ever if I can help it.

If it is truly b/c Bonnie misses your son, then, you should see results with Mazer's ideas. Also try to get her to play with you to re-direct her affections...

Please keep us posted,
Anne-Marie

Thank you all for the excellent suggestions! Son is actually still in the house - just in a different room. (Although DH was gone for a week when the grooming started the second time.) I will try the Feliway & fish oil. Good idea to put one of their beds in the new office - this may help greatly!

I had never heard of the Tellington touch method and it sounds interesting. I see that it works for car sickness - wonder if it would help me & DS?!? Thanks again & I will let you know what happens. The second steroid shot will probably wear off in 3-4 weeks.

Tellington touch is much like using acupressure on people...which can help relieve stress and increase blood flow among other things like relieve pain. I also recommend Rescue Remedy for people (as well as dogs) which can cut stress considerable.
My friend did not like the side effects of her anti depressants, so she went off them only to find out the depression returned, I suggested Rescue Remedy and either Chiropractic, acupuncture or acupressure - she reports like is much more colorful now - Now back to the pets.