When do you know it's healed? When to switch from daily Miralax to a more high-fiber diet?

I think I have a small posterior/lateral fissure (sharp pain, blood, etc) from a few days of dehydration and poor diet. It happened on 11/20 and retore the next day, and another small retear on 11/23. I immediately upped my water intake but it didnt fix my hard tipped stools, which caused discomfort but no more tearing.

I've been taking miralax for the past 7 days or so and plan to keep taking it for another 3-4, it has helped so much, my stools have been soft and narrow and now I have no symptoms. But I dont want to re-injure myself.

I'd like to get back to my usual high fiber diet and take my metamucil/psyllium again, which Ive been avoiding because it produces bulky stools. How do I know when I've healed?