How to deal with career fears with a rocky relationship?

Hello. I (26f, 4yoe swe) have hit a sort of a rough patch (going on and off for 2y) with my bf of 4yrs (25m, also 4yoe swe). I recently got a promo at work.

That relationship anxiety has started to bleed into my work. I have become forgetful, am underperforming. I am hating how I'm working, pretty sure others are seeing it too. The underperformance is filling me with dread. To an extent that I can't open my laptop. I have lost interest in my hobbies as well. How do I navigate this?

My priority right now is to get back on track career-wise. I like this job. It has been 1.5-2 months since I started going off track like this.