Would love some thoughts and insights about this situation/how to handle my dog being convinced our house is haunted. I feel out of ideas and have no clue if I'm doing the right things, or need to try a new tactic.

Context/probable stressors: My dog (8, spayed female pit/german shep mix) and I have lived in this house for about 2 and a half years. She is with me part time and across the street with my ex the other half of the time- we have a consistent 2 week on/off schedule and after an initial settling in period, she's always loved this house and done great here. She would usually sleep in bed with me, but often felt just as comfortable sleeping out on the couch on her own.

This summer she had some stressful events. In June, she had an TPLO surgery which has an extensive recovery period where she mostly had to be in a pen/restricted activity for several months. In August, my housemate moved out and my partner moved in (she is very bonded with my partner). Obviously some things changed in the house when he moved in, like the living room arrangement and now there's two beds we alternate between.
After the surgery confinement was over, she had a regression of separation anxiety (dealt with when she was a recently rescued pup, and saw it come back briefly after the first time she had this surgery). Then, she started having nighttime anxiety- she started waking me up panting, pacing, shaking climbing on top of me scared of seemingly nothing. She refuses to sleep in the living room alone now.

Now, it's anxiety about EVERY little noise in the house.... the fridge or heat turning on, the creak of a floorboard, acorns falling on the roof, the wind, literally any small noise... she tries to climb on top of us, pants, paces, sometimes drools. Mostly, she just wants to sit on the porch or in the yard to escape any scary house noises even in freezing cold weather.

I feel terrible for her, especially because I know she is home alone several days a week and probably has just as hard of a time when she's there alone because she can't go outside. No destructive behavior (honestly, that's never been like her, though). It feels like each of these types of anxiety are feeding each other and now she's just a mess almost all the time.

Across the street, my ex says she is having a slight uptick of noise and nighttime anxiety but nothing nearly as bad as she's having here (his house is also just less creaky and he works from home).

What I've tried: She takes a CBD (Charlotte's Web Calming) daily (and has for years), Adaptil plugin near the couch area (which is her preferred safe space), white noisemaker, her thundershirt which usually helps a lot, got her a new comfier bed in case it's a pain issue, sometimes I have given her a gabapentin overnight just to help her sleep and, honestly, because I need to get a solid night's sleep.

Redirecting to a chew (she's too anxious usually). I've tried saying "it's okay", I tried for a few weeks redirecting her to her safe space every time she would come find me due to anxiety. My tactic lately has been to firmly tell her to lay down each time, and then reward/patpat/goodgirl as soon as she lays down and that's it. None of it seems to be working, or it will seem to work for a few days and then stops being effective. She could probably use more exercise in general, but even when she's tuckered out from a hike she's not really any less anxious about the house.

A daily anxiety med is a tough solution because my ex is really bad about remembering to give her meds, and I don't want her having cold turkey drop offs of a psych meds every time she goes to him. I've heard about noise desensitization, but it's literally any and every noise so no clue where to even start with that.
Short of, like, moving (not an option until next August) or just having her stay with my ex full time (not a good option), I feel run out of strategies. Any insight/advice welcome!