Larry, sorry for your loss. Such experiences are never welcome, even if they can sometimes help to teach us certain lessons.
I have been considering how to respond to your post. As I understand it, Yang Jun teaches that you want to be calm when you do Taijiquan. I believe that is because Taiji strategy implies the opposite of the ferocity that many hard styles call for.
Grief can induce a tendency to a certain type of calm, if it is not excessive.
I think that any strong emotion tends to bias our engagement with reality along certain paths. The emotions are not good or bad in themselves, only a disproportionate excess or lack of emotion would be bad.
According to Traditional Chinese Medicine ("TCM"), grief is said to affect the "lungs" or "lung system." Some of TCM theories have been incorporated into Yang Style, but how much you may want to follow the other aspects of TCM may depend on your particular tradition, interests, and beliefs.
If your "lungs" are weakened, I would guess that it would be hard for your Qi to rise and easy for it to sink. The cost of this, however, might be a diminished capacity to raise your jingshen ("vital spirit," "morale," or "elan"). Qi, jing, and shen are interrelated.
My experience of grief is that it shakes me out of certain complacencies. Detaching myself from certain things is a good thing as long as I reattach myself to certain other things. Shaking my complacencies about the form allows me to feel the ground differently and let go more.
I think that grief can also help you to allow the form to do more work by itself with less controlling interference from the thinking mind (i.e., using more wuwei). Since the nature of the form should impose its own movement and movement principles, the less we add, the better from a certain viewpoint.
Ultimately, I think we want to work towards awareness of a dynamic balance that does not require a particular balance point.