I'm sorry it's so painful :(
Ideally you would have a therapist who could help you navigate this, but I understand that you don't currently have the means, as you mentioned in another comment.
So I think the next best thing is to learn about ERP (exposure response prevention), which is what most OCD specialists would likely have you do. There's a good YouTube channel called "OCD and Anxiety" that has a lot of free videos about it. You'd probably benefit most by searching for ROCD videos on that channel.
As for what you can do right now, try to recognize what's going on here:
1. You are experiencing intrusive thoughts about whether or not you actually love your parter.
2. These thoughts are making you anxious.
3. You are trying to get rid of the thoughts and anxiety through compulsive behaviors (in your case it sounds like rumination and reassurance seeking).
4. This of course doesn't work (at least, not for long) and when the thoughts return, you become even more anxious.
Take some time to really reflect on this, as painful as it feels. This is the quintessential obsession/compulsion cycle that drives OCD.
Right now, you're attempting to escape this cycle by addressing 1 and 2 (the thoughts and anxiety). The goal of ERP treatment, however, is to understand that 1 and 2 aren't the problem here. The problem is number 3: the compulsive behavior. The way to escape the cycle is to remove number 3.
If you've been part of this community for any amount of time, I'm sure you've read that "thoughts are just thoughts," and there's a reason that gets repeated so often here. People who get caught up in the OCD cycle put SO MUCH weight on thoughts, when in reality thoughts really don't mean much at all. They're actually just the brain's best guess as to what is important right now based in your surroundings, feelings, and countless other conditions. The key word here is GUESS.
When you compulsively try to suppress or debate with a thought, all you're really doing is training the brain to label that thought as important. The more you do it, the stronger that label becomes. The stronger that label is, the more anxious you feel when the thought arrives.
So what do you do? The goal is to learn to allow these thoughts to exist without resistance, and to allow the anxiety to come and go. This is of course easier said than done, and takes plenty of practice, but it becomes easier over time. Mindfulness techniques help immensely with this process. One could even argue that ERP is a form of mindfulness. Compulsions are a way of rejecting how you currently feel in the moment. To bring yourself right into the present moment is to face the anxiety head on, and show the brain that those thoughts and feelings aren't dangerous.
A very quick exercise that may help right in this moment is to really, really observe what you're PHYSICALLY feeling. Where do you feel this anxiety? In your stomach? Your forehead? Your chest? Don't try to get rid of it, just investigate it as if you're a curious martian who just inhabited a human body. Describe what you're feeling to yourself: "chest feels hot," "tingling in the stomach," "tightness in the forehead," etc. Allow it to all to be there.
To summarize:
- When you have the means to do so, please consider an OCD specialist.
- Learn about ERP and mindfulness techniques.
- Know that the thoughts, however scary they may be, are not a problem. They are in no way concrete evidence for anything.
- Know that resistance of these thoughts and anxiety is what is fueling the fire.
- In moments of panic, bring yourself into the present moment by paying attention to what you physically feel without any resistance.
I hope some of this is helpful.
