First of all.... I really get that you love your friend from what you’ve written and that the two of you are very close and that’s a great relationship to have. But....with all good intentions she’s completely crossing your boundaries by insisting that what works for her will work for you.
My T is very keen to get me into emdr. Almost excitedly so (I know from a view of her seeing someone suffer and knowing a technique that helps many) We started about 3 months in and I absolutely hated it. I found it retraumatizing, it would make me spiral off into weeks of dissociation. I’m not saying emdr doesn’t work or even that it didn’t for me, but I definitely know, I’m just not ready to go there yet. Maybe someday, or maybe not. And that’s ok.
This is YOUR healing journey! It can only move at YOUR pace and to the places you are ready for it to go to.

You know your friend best, but if it was a close relationship of mine in this situation, knowing how I hate confrontation, I would likely write a very loving email explaining how happy I am my dear friend is finding help where she needs it and that it is working for her. And I really appreciate how much she cares and wants to share her sucsss journey with me. However, emdr isn’t something I’m ready for just yet and although her intentions are encouraging, I find it very stressful to manage when she keeps pushing that one method in front of me. There are many forms of therapy, it’s not a one size fits all and right now, I am happy working where I am.
Most of the time people mean SO well that they’re blinded by your subtle reactions to turn it down. Usually a good clear explanation is all it takes. Unless of course that relationship is toxic, then there’s often no amount of explaining that helps.