Getting a vaginal orgasm is as much a mental thing as it is a physical thing. If you aren't in 'the zone' it probably wont work. So that might be something to take into consideration. I don't know your situation, but it might have something to do with it, so I thought I'd share it.
With normal straight up penetration, you might not give your g-stop the attention it deserves. There are a lot of g-spot vibrators out there, you might give one of those a try.
I'm just a guy, so I can't share how it's supposed to feel, I can share what I did with my GF in order to 'fix' a similar problem.
She enjoyed PIV sex but she wasn't able to cum from it. Fingering her inside wasn't something she did and while she did read about the g-spot she never put in the time to explore it. So when we started dating we started to work on this. She was exited because she might experience a orgasm that wasn't due to clitoral stimulation and I got to play around with her lady part to my hearts desire. Win win, id say.
Anyhow, I started to introduce a few things over a span over several months. At first just inserting a finger during forplay. When she got used to that, I'd massage her from the inside while eating her out. At first she didn't like that, now she goes crazy about it. We'd look up positions that would focus the thrusting on the G-spot during PIV. At first that didn't do a whole lot to make her cum, but it did give a boost to our sex life.
So after a good while she started to enjoy the g-spot stimulation, but still couldn't orgasm from it. So we bought a g-spot vibrator with a wireless remote. Worked wonder for her just to get used to the sensation of continuous g-spot stimulation. Combining this thing while eating her out gave (and gives) her some great orgasms.
Another thing that helped her was getting off with clitoral stimulation while I was inside her. Not sure why this was such a help, but she got way more responsive after doing this every now and again.
So because of this 'research' she is now able to orgasm from PIV. It hasn't become a sure thing or anything. She won't cum from it if we have a quicky. But when we put in the time it works like a charm.
I really feel for you. 8 years without improving sexually sounds very frustrating. Does your bf know you feel this way? What is his view on this?