I have been with my girlfriend for over 10 years.
We are very fulfilled sexually, there have never been any problems there.

We practiced anal at the beginning of our relationship, for a few years and then we ended up stopping due to some disappointment.
we tried again from time to time but it was impossible, it hurt or it didn't fit.

And then last week, she went out with her best friend, me working the next day I didn't go out. She had planned to come home early, so I went to bed quietly.
Finally she came home around 4am without telling me, she had clearly had a lot to drink.
She slips into bed and wakes me up, she was really very very excited as she rarely is... she sticks to me and while jerk my cock gently says to me "I want you to put it in my ass" I hesitate a little but the invitation is a good one to take...

so I put her on doggystyle, I look at her and she is already soaked... her ass already seems dilated to me. I place my dick against her anus, I put a little saliva and I press gently, it goes in in one go... I can penetrate her normally from the start, her anus is already completely open...

She tells me "harder", so I hit harder, she tells me "go ahead again", so I fuck her ass for half an hour, I hit like I don't do in her pussy, I was afraid of hurting her, but at no time did her anus seem contracted... it was open and dilated from the start, I cum everything inside after having pushed it with as much force as I had.
I thought that the next day she would have been in pain, after the past pleasure sometimes we regret it, ultimately no problem.

I tell myself that we can start again, even if she doesn't often come home drunk and excited like that..

I'm not English so I did my best to explain well