maybe you can write a new post about the same thing and hopefully those that posted before will do so again. you can also if you remember what the post was about and know who posted what you need you can ask them

showing your T what someone else posted here if I remember the rules right isnt allowed without asking that person who posted for permission to do so. but maybe you can paraphrase what you do remember and ask your therapist for clarification on that topic and tell them how that topic applies to you.

I'm a therapist and personally I would rather hear from the client what the clients impressions are of what they find online and how they think it applied to them rather than waste that clients valuable therapy time read someone elses postings.

since you know what the thread was and what posting you want to show your therapist maybe you can write about that in your journal and show your therapist your journal. therapists love reading clients journals. it shows the therapist where the clients mind is at, any problems the client is having and possible topics to cover during therapy.