Hi, Mam, and I also want to welcome you to PC.
All my life, I've been sensitive to noise, and I would have trouble in the situation you describe in your apartment. If you wish to continue to live there, and if complaints to the supervisor of the apartments (is there one?) do no good, then you might try adjusting to this in the manner that I have done at times in the past.
I teach middle school art, and for many years my classroom was next door to the band room. People would come into my room to visit, and the first thing they would ask is "How do you stand this noise?" And I would laugh and say, honestly, "I don't even hear it anymore." Which was true. I simply tuned it out. I don't know how I managed to do this, as I am truly sensitive to noise....can't abide noise in my home. But if I were in a situation you describe, I would attempt to do this.
I also recognize much of my own symptoms in what you describe regarding change. I have a lot of anxiety over such things as well...to the point that I avoid change if at all possible.
But!!!, when there is a situation beyond our control, such as the noise if you choose to remain in this apartment, perhaps practice tuning it out if at all possible.
Patty