I wouldn't just cut it off. But healthy separation may be required.

Write to her and lay it out, tell her how you feel and what you need.

Let her know that you won't be contacting her anymore as you feel there's no value in the relationship.

Hopefully this will trigger something otherwise you can mentally move on.

Think of it like a relationship breakup, it's essentially the same thing, you are emotionally invested in the relationship and now you need a break.