Hi, I'm glad that you managed to relax last night, hold on to that feeling. Of course, you will have relapses, but you know that you can regain perspective. I always find it very helpful to remember that, however hard it is to understand when I am in the grip of an anxiety, it is an anxiety problem, and finding a way to relax and refocus will help me to put it back into perspective.
This may sound ridiculous, but I have found that repetitive hobbies such as knitting or painting have a relaxing effect by drawing me in to concentrating on something else.
There are some good "mindfulness for OCD" videos on you tube. Even if you are cynical about mindfulness, I find that it is comforting just to watch a video of someone that I know understands talking about the problem in a compassionate way.
I don't know enough about your relationship with your ex to really have an opinion, but maybe it would be helpful for him to read the section in the book "Overcoming OCD" which is addressed to concerned family and friends.
This emphasises that a supportive approach does not mean pandering to the OCD sufferers worries-this can be difficult sometimes, when a person is begging for reassurance about something.
I find that is helpful for me to be really clear to friends that I do want them to be supportive when I am feeling low, but this does not mean sitting and mulling over the content of my worries with me and trying to find solutions to them (I won't go into the kinds of things I worry about).
I would rather talk about anything else and I find that focussing on other things helps the anxiety to fade. I suppose it is about getting myself out of my own head and grounding myself in reality-so even having a chat with someone in the local shop and "acting" like calm person has the effect of making me calmer.
As I said, I really don't know what sort of person your ex is, so I am very cautious to say this, but maybe your OCD is trying to "recruit" him by asking him to behave in certain ways that in the short term reduce your worry, and that is what he is reacting to when he says he can't live with your rules anymore. In other words, there may be something positive to be gained from his uncompromising attitude, if he can also be compassionate about the problem itself. Its just a thought.