Bonan, I have a dick only about 0.5” longer than yours (about 7.75”), and I had to be very careful with 33% of the women I have been with because I was a little too long for them. Over time some of them stretched, but some did not. Half of them liked it, and half of them hated it, so with those I had to be careful and not stick it in all the way. It used to bother me before because like you I liked it all they way deep, but somehow over time I also found pleasure in not sticking in all the way.
Just for reference, 33% of them were a little too deep, and 33% were just right.
Another thing to consider is that many women are more sensitive in the front portion of their vagina, so sticking in deeper does nothing for them. Also, many are mostly sensitive on the outside part (like lips and clitoris). If you are short or just right then you will be hitting those areas and she will like it. If you are too long, then those areas will not get stimulated, and some women even use their fingers to stimulate their clit.