Because you have significant symptoms of OCD, they cannot be ruled out as the cause. By your own admission, you have “extreme” anxiety, obsessive thinking and engage in avoidance behaviors. Those are the main symptoms of OCD. Until your symptoms dissipate, OCD seems like the most logical explanation.
Let’s also consider the statement “I understand how wrong it is but I’m pretty sure it’s there and I’m horrified,” the operative phrase being “pretty sure.” Pretty sure indicates that you are not certain. Thus, you are not certain that these are your thoughts. That would make them unwanted and intrusive, definite symptoms of OCD.
In addition, you asked “how the hell could my sexuality change so drastically?” The answer is that it can’t and doesn’t. You also find the thoughts horrifying. All more evidence of OCD.
There is a type of OCD called pedophile OCD (POCD). It’s not an official diagnosis but it’s a trend that researchers have noticed. It involves people with OCD who are primarily obsessed with the idea that they are pedophiles. People with pedophile OCD are not pedophiles. You can read more about it on this website.
It is also important to consider the nature of anxiety disorders. They induce fear and panic about things that should not cause fear and panic. They lead one to consider possibilities that should not be considered. They can cause you think certain things are true that are not true.
You were diagnosed with OCD but said nothing about treatment. If you are not in treatment, then it is best to start right away. Anxiety disorders are highly responsive to both psychotherapy and medication. Psychotherapy will help you to focus on what is real and true. Click the “Find Help” tab, at this top of this page, to find a local specialist in anxiety.
Finally, it is impossible to make definitive diagnoses over the internet but based on the information you have provided, the evidence would suggest that OCD is at the heart of this problem. Contacting a mental health professional, who specializes in anxiety disorders, will help you to quickly resolve this problem. Good luck.
Dr. Kristina Randle