Your wife sounds very similar and let me tell you I had 6 doctors tell me my sickness was psychosomatic. One later confessed that he had no earthly idea what was the matter with me but rather than admit it, he said I was crazy.
I would say, don't accept them saying you are crazy. If you watch Mystery Diagnosis you will see case after case of people who are told they are crazy and they are not.
I am so thankful my neurologist has been so thorough; she has ordered test after test because she knew something was wrong but couldn't put her finger on it. I did have hyperreflexia and clonus which were tangible things she could see, everything else was my word. But my first neurologist saw me repeatedly and never even tested my reflexes and said he couldn't find anything wrong.
I am very fatigued all the time (and I used to be very very active), spend a good chunk of the day propped up in bed, can sit up for a few hours then I am wiped out. I can walk maybe 10 steps on a good day holding on to things, but I am wiped out afterward. I get spells of shaking tremors and numbness and paralysis and spasticity that last about like your wife's do and they are very much brought on by too much exertion or emotion. I also have trouble breating due to a tight constricting feeling around my chest when these spells happen. And sometimes I break out in what appears to be hives.
My neuro sent me to an endocrinologist to check for endocrine disease and I just found out yesterday that two of the tests came back weakly positive: adrenal antibodies and celiac disease, so I now have three sets of antibodies found in smallish numbers, a positive test for autonomic dysfunction, and positive for demyelinating polyneuropathy, but the results of the tests were strange because my adrenal function at that moment seemed to be fine. He is running more tests, but I sometimes wonder if I am a "new disease". Maybe your wife and I will be case 1 and 2 of some newly discovered illness.
My advice to you is find a doctor who will listen and really examine and test your wife. And let me know how it is going. And one other thing, my doc traced back my autoimmune illness to dysentery almost two years ago. You might start journalling her symptoms and retracing her history to when the problem started.
Keep pursuing an answer and may God direct your steps.
I have a question, My wife has similar symptoms and the Doctors do not know what it is. Let me just ask you to see if everything is the same, Do you have Weakness of the arms, and legs all the time, and fatigue all the time, but fatigue increases if you walk around for a little bit, talk for a while, not sleep enough, or don't eat, My wife, if she gets to exhausted, or too weak she gets paralysed from the lymbs and her face. Does that happen to you. Her complete paralysis normaly lasts anywhere from like 30 minutes to 4 or 5 hours. My wife was told by her doc that it was phsycological, but I do not think it is, it seems that if the doctors do not know what is wrong with you, they automatically say is phsycological.