It could be she doesn't enjoy giving bj's, it could be she has TMJ, it could be she's not relaxed or in a position that is comfortable for her, it could be ......... who knows?

You'll have to ask that woman.

I have TMJ disorder, but I can go for a long time. I've learned to adapt.

Maybe she just doesn't really enjoy doing it.

Or you have a really big..........dick......?

OTM - You're so smart. He probably has a really huge dick.

I mean, I love to give oral and receive but there are certain things to take into consideration...

Is the man's hygiene up to snuff? Is the woman's? Have both parties discussed expectations when it comes to oral? Does she know he wants oral? Is she willing to give it?

Get her to lick it like a cocksicle or popsicle...

I don't think its because of a really big dick because there are all all types of ways to do it.
Do you think it bores her? Her attention is shot? Or doesn't care for it?
Ask her

I have TMJ and my late husband was very one sided when it came to this.....he did not appreciate it though he loved it. By that i mean, HE had issues ( E.D.) and refused to admit that or deal with that....and instead expected hours and hours and hours of receiving it.
and with TMJ , i can tell you , for me, it was miserable. Painful as h***. and the ironic part is how much i love doing it.
the person i am now with, i have had no jaw pain at all ( and he is bigger than late husband ) but , is very much equal in bed and also knows how to give and receive without anyone suffering pain. What a blessing !
Now, this is my first day looking at posts in this group so i don't anything about you but the way you asked it, hmmm.......reminds me of my husband. He was very macho, and quick to put down how women "are"; in other words, "talk too much, nag too much, " etc....so the dynamics there were pretty much impossible to conquer in the pleasure dept. He has 2 brothers, very similar in views and very similar in that kind of problem. I am very close to their wives....lol