Did I SA my sister

We are both in our 50s now but when I was 11 and she was 8 there was an isolated incident.

We were playing "house" and we would kiss sometimes. This particular time it escalated into us both wearing only underwear bottoms and kind of rolling around on the bed and I ejaculated and ran out of the room.

This was not at all my intended outcome.

At no time did either of our privates get touched by the other. Nor were they exposed.

Nothing remotely like this ever happened again.

Nevertheless she tried to blackmail me over this til I had to tell our folks about a decade ago.

She was threatening to tell my partner recently. So I had to tell her too.

My sister and I do not speak currently.

I carried around tremendous guilt for this for decades. In my 20s I self harmed focused on this.

Ive also had multiple suicide attempts, the guilt of this incident contributed to.

I just want some honest and frank opinions about this.

And what am I supposed to do about it now?

I have apologized. I have tried to be a good adult sibling for 30 odd years.

Thanks