Learn psychology. That will keep you sane. Philosophy will always remain subordinate to it.

Meister Eckhart there, was referring to mystical experiences. (Hallucinations?) I never had any, so can't say much about it.

Some spiritual traditions describe consciousness as an ultimate subject, but i disagree with that. When thee feeling of individuality ceases, objects also. All remains is emptiness. Like the universe never came into existence.

Some might describe it differently, but this is how i experienced it.

Removing that guy in your head, looking through your eyes. :) That's what meditation is for originally.

Sadly, there are even more frightening things than solipsism.

As i understand it, solipsism presupposes a subject.

While perennialism's sole aim is removing subjectivity completely.

A solipsist refuse to learn from others' experiences.
We simply need to believe that others exists to function properly.
Maintaining a solipsist view, eventually will ruin your mental health to the point that you start dissociating, or even experience psychosis.
Your body will FORCE you to drop solipsism, otherwise you cannot recover. Simple as that.
The body is king. If you turn against it, your brain will shut your thinking down. :)

Sorry for my bad english.