OCD around penis size: Please help me

Hello, I just created this account because I have been struggling with this for a couple of months now, and I can't tell anyone in real life about it. My life has been consumed by an obsession over my penis size. I know I am now well-endowed: I am somewhere around 4-inches (give/take a centimeter) so I am not sure that this counts as BDD. To my understanding, people with BDD regarding this topic are average sized or larger, but they are convinced they are small due to porn or other factors. However, in my case my fears are true which makes me think it isn't BDD.

I have been previously diagnosed with OCD and have been receiving treatment for a while, but it seems that my brain has latched onto this topic and I cannot shake it. I have two main compulsions: constantly measuring my penis and Googling women's comments on small penises. I've found it difficult to measure my length due to an upward curve (it runs parallel to my body) and my pubic fat, so I am paranoid that in reality I measure under 4 inches, which may very well be true. Any time I try to masturbate I have to go grab the ruler so I can check and hopefully measure "the correct way" for once.

The Googling stems from my fear of not being able to satisfy a woman with the equipment I have. I worry that in the event I ever get intimate with a woman, she will either reject me due to my size, or flat out humiliate me. Sometimes I see reassuring comments from women saying the best sex they ever had was with a guy in the 3-4 inch range, but there are often posts complaining about partners my size. I also get really upset after stumbling upon posts from cuckolds who aren't well-endowed, because it makes me paranoid that I will be doomed to that lifestyle.

I know it is impossible to change my penis size; the only thing I can do is come to terms with it. But lately it has completely devastated me and my life has been consumed by this obsession. Is this considered a form of BDD? And can anybody offer me some hope/advice on how to overcome this? Thank you for reading this far, I know a lot of this is TMI. I would greatly appreciate any advice because I am really struggling right now.