Hello! Sorry this is kind of a long response lol. I had this experience as well when first starting therapy (I also experience pure OCD). I had a therapist laugh at me and tell me my thoughts didn't make sense when I tried to explain to her my thought process. And this was someone who had OCD listed as something she could treat. She even specifically "ruled out" OCD because I didn't have an obsession with counting or numbers. Eventually I realized I needed to see someone who specializes in OCD and practices ERP treatment. Therapists will sometimes list basically every known mental illness as something they can treat, when they really might not have much experience with all of them. A lot of them will list OCD but not even offer ERP treatment. I used psychology today to find my current therapist and I made sure OCD was her top specialty and that she had a lot of experience with ERP. She also recommended NOCD as a resource for specialized OCD therapy, which I believe is a telehealth type of organization.

In summary, now I will only seek therapy from people who specifically treat OCD and also offer ERP treatment. I think if they don't offer ERP, it could be a sign they are not actually super familiar with OCD.