Hello Summer Daze: Well... the Skeezyks hasn't had a lot of experience with this.

I've seen a few therapists for brief periods of time over the years. Most of them weren't worth the bother.

The last one I saw was, by far & away, the best of the lot... still not great... but the best one I saw. One evening I got myself worked up into a lather over something or other...

I don't recall what it was. Anyway, I called her on the phone & told her I wasn't coming back... & that was that.
Personally, I would recommend that, if you feel you can, the best thing to do would be to have one final meeting with your T & tell him you plan to terminate therapy... being as honest as you feel you can be with regard to your reasons. However, therapy is a business arrangement. You (or someone else) are paying this individual to provide you with mental health therapy services. So, if attending one last session simply feels too threatening to you, there's certainly nothing wrong with just sending a text. It's really your choice.
From my perspective, the thing you need to consider here is how you will feel about how you ended the relationship once it's all said & done. In my case, I simply never heard from my former therapist again... which is fine with me.