This is an issue that I too am considering, but I do not have children... so it's not an easy decision to make. There is a blog that I follow, written by a woman who has had a hyseterectomy, and she writes very candidly and honeslty about the issues that have arisen. Here is the link: myendojourney.wordpress.com/
I have found it helpful, and she has had a positive experience from it.Sometimes these sights can be a bit 'doom and gloom' and not many people write about having success stories, but she does. It goes to show, there is light at the end of the tunnel. For some people anyway. I know it doesnt work for everyone. We can hope though!
Like you, I ask myself "what if I go through all of that, major surgery, and it doesnt work?". What a massive risk to take if the outcome is no better then what I feel right now. But I suppose sometimes in life, you have to just jump in, take the risk, and hope for the best. But it's definitely something that needs to be thought about in great, GREAT detail and depth. If you havent come to a decision by the time your appointment comes up, just say you need a bit longer. Take your time.
Also, re Prostap (I assume thats the injection that you are talking about), I spoke to a nurse when I had my last injection last week, who told me that she has been giving the injections to a woman for the last 10 years! So saying you are only allowed it twice is absolute nonsense. It sounds to me as though they are concerned about money! You know the NHS. Each injection is £75, so they dont want to keep giving and keep giving.
The injections have been working quite well for me, so I spoke to her with concerns about having to give them up in 6 months. I said I didnt want to go back to how poorly I was before. She said that it wasnt an issue. She said, under the discrecion of the consultant, you can have them for as long as you like, but, that you have to keep having bone tests at the same time to check that its not effecting your bones. So, my advice is; dont take no for an answer. Because it is possible! And if they still say no, then get a new consultant... who will allow you to keep having them. It'll give you more time to think about your hysterctomy too.
Hope that helps