Also, another thing to consider if you're gonna go down the 'comparing' route -
From a sheer numbers perspective and mathematical deviation, if a woman has sex with 10-20 partners, there is a very good likely hood she's gotten close to one end of the curve or the other in terms of ALL physical traits. The deviation doesn't go in the other direction Men -> Women because of sexual choice in the market place being tilted towards women.
If a girl has slept with a dozen guys or so, and the more guys she sleeps with, the more likely it will be she'll encounter a dick on the far end of the size deviation.
The good thing for me is, I'm sort of over it, especially the insecurity of it.
Now, I'm not in a position to get back into a relationship again, and if I WERE to pursue another 'committed' relationship, a low count or at least interpreting that she's been at least SOMEWHAT nice of a girl would be ideal in the candidate I would choose.
Short quip:
Since I've been single these last 2 years, penis size be damned, I've plowed more pussy than I have in the last 10 years (#humble brag - I average about 2 new girls a month - got into Pickup and Seduction).
Now all that I care about (even though I still practice PE) is just having sex with beautiful women that I 'click' with. I'm fully aware that there are guys with big dicks out there that have NO GAME.
I generally bang every girl that I like that I meet, regardless of who they're friends with or how I know them. I fuck them like it's the last time I'm ever going to have sex ever again. I then bury my head in my work and my ambitions and being the best version of me that I can, and by doing so the women constantly hit me up.
Since being single, and being at a modest 7" (Modest in the PE community) I've gotten more "OMG, your cock is NICE" and "Wow, you're pretty big, i like it!".
I'm blabbing, but to make a long story short, if you're in a relationship - don't ask about her previous dicks.
If you're single, just plow on brothers. Don't let your insecurities stop you from banging tons of pussy!