You're playing an odds game, it's about 50/50 each time, yes your eggs are getting old and smell of sulphur , I feel I can say that, having been in the same boat! But know what??? The next egg could be the "golden one"
It's all down to what you think - can you cope with a few more early losses? Can you get your self into the frame of mind where you think that a positive test just means a "chance" rather than a baby? I really had to do this, my first m/c at age 40 1/2 (MMC at 12 weeks, baby died a few days before at 11+4) was so devastating, but decided to carry on, became progresively more pesimistic with each positive test, to protect my own sanity, but also tried to take the positive from each pregnancy - that I was at age 40, 41, 42, able to get pregnant, easily (about every 3rd cycle). had 4 m/c that the hospital were involved with (12wk,9wk, 2 at 6wk), plus a few (awful to say I can't remember how many, "chemical" pregs at between 4 1/2 and 6 weeks) which I just dealt with at home. It got so I hated the EPAC staff and with my current pregnancy (now 22 weeks!!!!! I will be almost 43 when he's born), they were very, very negative (initial slow heart rate at 7 week scan) and they actually told me to stop trying!!!! Really felt like saying "fuck off, it's my body!"
So I ramble, but I guess what I'm saying is, try if you want to, be prepared for the worst but you know, you could do it , maybe even this time, though I know you think not much hope and things have already gone wrong, but you never know.
On a practical note, have you had any consultant advice regarding increasing your chances? after 9wk mc (which had trisomy14, very rare and lethel), saw consultant who said, non disjunction causes most mc in older women, and he thought that was the likely cause of all my mc (the chromosomes dont seperate properly,and you get various trisomys such as 21, 18, extra x or y), and most of these are fatal in the early weeks, but there is something you can do to reduce the chances of non-disjunction.
I was put on 5mg per day of folic acid (a very large dose, about 10times the usual daily intake), as this has been shown to reduce the number abnormal embryos.
Also I was put on mini asprin (75mg per day), to be taken as soon as you get a positive test, all through pregnancy as he said clotting and immune issues you develope as you get older can stop the pregnancy implanting properly, leading to m/c or an increased risk of growth restriction/pre-eclampsia.
Maybe you should ask about those? It may make the difference.
Good luck, whatever you decide.