In my opinion, this depression is not something related to lack of grounding.
Due to my previous experience with shamanism, i think that this could be caused by working in the city and not in nature:
when one does a ritual, he opens himself to the spirits who naturally live in that particular environment.
In urban places, depression spirits are very common.
On the contrary, practicing in nature is very beneficial and you will never experience depression spirits simply because they cannot live there!
Maybe, I'll try in the future adding some banish rituals, but it's strange that GGC didn't instruct on doing so.
I'm just wondering how could Arzel give permission to such entities to interfere with the practitioner!