What would you do if you were in my position?

I've been with my boyfriend for 2.5 years and although we've had our ups and downs, we've always worked through things.

To cut a long story short, his brother came into my place of work but I had already finished and apparently a colleague of mine had said I hadn't been in all day (I finished at 12pm as I was owed some time).

Now my boyfriend thinks I'm lying to him and he's taking his brothers word and my colleagues over mine even after I've shown him my rota. I work in a big store so it's pretty easy to go a whole shift without seeing someone let alone half a shift.

I know for a fact I was working and I'm so mad at him for not believing me and thinking I may be cheating.

How would you handle this situation?
What would you do if you were in my position?
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