What to tell significant other?

It’s not necessarily dishonest if you don’t tell him. You don’t owe him an explanation of anything. Your experience with OCD is yours and yours only. I totally understand the whole “my significant other won’t understand the themes I struggle with” or “I want the support from my significant other so I think telling them is the right thing to do” narratives, but if you really want him to somewhat understand, send him YouTube videos or articles that describe the disorder and/or its themes clearly.

Personally, I told my now husband, at the time boyfriend, about how my mostly pure-O OCD works, my common themes, my history with OCD and anxiety and panic attacks. He’s understanding although I don’t think he fully gets it, but that’s okay because he’s never had those experiences himself. I felt comfortable sharing with him and so I told him a lot about it. When I have OCD or panic flare ups, I let him know and he’s supportive. You can try telling him an overview and then if you feel more comfortable, let him know more.

The other comments are very good and I do agree with them, but I wanted to add some things since I relate a lot to you! One of the biggest themes I've dealt with, and still do here and there, is POCD, so it was important for me to portray OCD as honestly and realistically as possible to my now fiancé because... well, I deal with taboo intrusive thoughts like a LOT of other sufferers. I tried my best to talk about OCD as a whole, and then mentioned that taboo themes were the most common (and they are, though do not cite me — this was something I learned over the course of multiple years of having the disorder!) and continued to discuss it with him. He didn't really get it at first, but he was very understanding and we've since had a lot more conversations about OCD as a whole while I've been dealing with a flare up. Try to remind yourself that, while he is your partner, he doesn't need to know every thought in your head. People without OCD have lots of thoughts and struggles that they do not divulge to their partners, and they typically do not attribute a moral standing to it (like being a bad person for "hiding" something)! My fiancé was the one who pointed this out to me in our own relationship, so maybe it can be of some help to you as well. Share what YOU are comfortable sharing, not what you feel you *need* to share — that feeling of urgency to tell him may be a compulsion, and that won't be helpful to you in the long run. Be kind to yourself, you're suffering with a very difficult disorder, but you're not alone. 🤍