Vision: Pretty obvious here.
Originality: I've seen the "bad girl breaks her therapist's rose tinted glasses" theme before. Your story is executed well in its own way, but your hotline worker lacks depth. It's not immediately noticeable, but she seems to exist in a vacuum with the sole purpose of foiling the main character. Joanna's barely been given her own voice before it's being trampled on.
That said, I realize this may come from personal experience or research on the total lack of quality control in these organizations. I myself tend to find positive psychologists somewhat useless and easy to ignore. They have their place but it is not around sick people.
Technique: Overall, better than anything else I've read in deviantart's collection of preteen diary entries/hetalia fanfiction. I know that's not saying much, but with a little editing this would actually be close to professional work.
The beginning is strong. But you should stay away from describing actions with their opposites. If you say "the couch fails to yield to my attempt to sink into it," the reader's mind skips over 'fails' and focuses on 'yield' and 'sink.' So before the word 'fail' clicks you're already imagining the action that shouldn't be happening. This becomes an awkward vision when you then talk about the bounce. Instead of saying what the cushions are not, say what they are. Things that are ordinary, like soft couches, don't need to be written about. Unusual things need to be the focus.
Similarly, people tend to open boxes with their hands, it would be notable if the main character were ripping off the tape without a tool or something.
The transition to the flashback is almost nonexistent. The reader isn't given any warning before being thrown back. The dialogue here is pretty good, and things seem to flow well. You might want to have others read it to see if it's too choppy, but it is realistic.
With the abrupt shift back to the present, things become very choppy. The descriptive sentences just seem to be thrown in there without something to unify them.
And then there's the issue with the phone worker. It's a good idea to get other people to read your work so they can pick out parts that feel funny. We always tend to miss something. I also tend to notice mistakes more often when I leave something sit for a while and come back to it. Editing turns obsessive when I am forced to be away from my work for long stretches of time.
The end is fairly strong. It seems like you just jump from scene to scene at times. Take these things a little slower. Sometimes those in-between moments can give you the right chance to get into your character's mind.
Impact: This is quality work. There is a lot of feeling left in you after reading it. Most things I don't even bother to read, let alone critique or comment.