You are a success story. Do you know that? Early intervention like you were fortunate to receive as a small child often helps children overcome autistic-like traits. That’s great.
I suspect your loved ones are referring to that early assessment because they don’t know how to help when you hit a rough patch and they take some comfort in having an “explanation” for your problems. The problem, then, isn’t your old diagnosis, but rather that the people who love you are upset that they don’t know how to help you.
The way out of this is to acknowledge their caring and to remind them that their love and support is all you need. You can also reassure them by following through on your intention to see a therapist. I’m sure that you are smart enough and insightful enough to make use of what the therapist has to offer.
As for your friend: I don’t think she is a “foe”. My guess is that she was trying to be helpful but made a mistake based on very out-dated information in your case. (If you were truly autistic, her advice would make sense.) Mistakes are human. We all make them now and then. She has generally been very helpful to you as only a good friend can be. Good friends are hard to find. Hold onto her. Have a heart to heart conversation with her about how her suggestion hasn’t been helpful and bring her up to date on your progress and successes.
As for being “different”: The fact is that we are all different in one way or another. Often it is those differences that make us interesting and even exciting to others. You lost sight of that somewhere along the line and your self-esteem has suffered. Do talk to the therapist about this. You can recover from that diminished self-esteem just as you recovered from autistic-like traits.
I wish you well.