Should I tell my gf's parents that I broke up with her because she cheated?

I just broke up with her early afternoon because she cheated. The problem is I've always gotten along with her family and parents from day 1. I was closed to those people and they felt like a second family to me. I will miss them all.

I'm usually not into telling others personal stuff but what I'm concerned about is there might be a chance she might lie to make it sound like I dump her suddenly for no reason so they can all think I'm such an inconsiderate jerk that broke her heart when it was the other way around. More than likely as the days passed by all of them are going to start going what happened, why are we distant and why we broke up.

In my position would it be right to be honest and tell them briefly the reason I broke it off? It hurts more because I was so close to thinking of proposing to her towards the ending of this year.
Yes, you should tell them
No, keep it to yourself
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+1 y
I've always been respectful to their daughter by the way and well she hurt me. She slept with not just another guy but two.
Should I tell my gf's parents that I broke up with her because she cheated?
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