There is so much pressure on women to be having drop of the hat orgasms from piv sex alone! The female orgasm is more about the mind, the male is more about the visual.
It took me a long time to orgasm with someone else in the room, although I never had any problems getting there myself. I needed to feel totally comfortable and trust the person I was with. We tried sex toys at first and that was my breakthrough. The rest followed easily!
But until my DH, I was only able to orgasm through manual/oral stimulation. Now I can actually manage it through piv sex and no stimulation. But this only happens when I am really in the mood and right place - I need to be on top, relaxed, not too tired etc. I also need to know that there's no pressure to - I get what you're saying about being watched!
I'd recommend starting off with a sex toy, if your OH is amenable (sadly they aren't always). Then try other methods. Start small and build up. Throughout it all, communicate! One thing I struggle to make my DH understand is that sometimes, just sex without orgasm is good for me - it's about the closeness and connecting. It's so important that you do not feel pressured.
I'd also really recommend spending some time with yourself, exploring what works, what makes you feel good and turns you on. Taking this knowledge into the bedroom with you will really pay off.
Finally, please don't believe everything you read! I just saw a post by by a lady claiming she has 10 orgasms in an hour. Good for her if she's telling the truth, but this is not a usual experience outside of a porno