I’m the avoidant one. How do I not hurt him if I decide to leave?

I’m the avoidant one in a 5-year relationship, and I’m struggling with whether to stay or leave. We’ve been long distance for the past year, and recently my partner has become much more certain about our future living together, saving for a house, etc. Instead of feeling excited, I got scared and started pulling away.

I started therapy and learned about avoidant attachment, and a lot of it makes sense. My partner and I have talked about it too.

But during this process, we’ve both said and done things that hurt each other. It has also brought some incompatibilities to the surface that weren’t as obvious before. I can’t tell if these are genuine reasons we shouldn’t be together, or if we’re just focusing more on each other’s shortcomings because we’re hurt right now.

At this point, maybe 60–70% of me wants to break up. When I imagine leaving, I feel a sense of freedom and relief but also a lot of sadness and regret. The other part of me still wants to understand myself better and see if we can work through our issues.

I don’t want to impulsively end a 5-year relationship because my instinct is to run when commitment gets real. But I also don’t want to keep him in limbo while I figure myself out.

For those who have been on the receiving end of an avoidant breakup: if I do decide to leave, what should I absolutely NOT do? What made your breakup more painful, and what do you wish your ex had done differently?
And for other avoidants: how did you know whether you genuinely wanted to leave or were just deactivating?