When do you accept you bought too small?

Cw: Feet!

I've had the boots since October. Worn regularly (on active days, not just sitting around), they're comfortable in all ways except on the instep. You can see the bruising in the picture.

I've been telling myself I just need to break them in and wait for them to stretch and soften but it's been this uncomfortable for long enough that I'm starting to dread wearing them.

Replace with a size up or persist and keep trying to wear these?