It's hot, some (probably most) women will never cum just from your cock no matter how long/thick/hard/experienced you are. Most (virtually all) women can make themselves cum by playing with their clit. I spent a year or so with a woman who found it very hard to cum, fingering her clit while fucking was probably her number one way of getting off, I suspect it would have worked wonders for my ex wife but she just had too many hangups to do anything like that during sex. You should be very happy that you are with a woman who is open enough to do this.
You don't for example want to spend 10 years with a woman who won't touch herself in front of you and thinks oral (either way) is out of the question after penetration.
My current Girlfriend cums very easily while I don't. Sometimes I stop after half an hour or so if I think I need a rest before i'm going to finish. Sometimes she wants to stop but often she starts frgging herself even though she has already cum a few times. Sometimes I try to help out with a finger or two but that has always been too "distracting". Last weeked she did this and I got between her legs and inserted three inches or so of my cock (I needed a rest, it didn't
, she went to stop so I could continue fucking, I said "no, you carry on" and stayed still while she frigged herself senseless, the tightest part of her engorged pussy gripping my g-spot rubbing cockhead and getting me as hard as a teenager as she had a huge shuddering orgasm. when her fingers left her clit I was rested and incredibly turned on. I fucked her as hard as i've ever fucked for a minute or so and I swear she never stopped cumming until after i'd had the best orgasm i've had in years.
She was actually talking about it the next day, something she never does