The treatment of OCD involves medicines as well as therapy. I don't know what you mean by positivity medications but for OCD the group of medicines called SSRIs work the best. They should be given in adequate doses to see the effect. Along with medications CBT can also help to a great extent.
Diabetes has to be managed in the usual way and any interactions in medicines for OCD with medicines you are taking for diabetes will be told to you by doctors. Lifestyle changes are recommended for any diabetic patient and will help you too. Plz take treatment for OCD.