Actually if you play with the extended ending DLC, you will notice that if you choose the destruction option it does not destroy all the tech or mass relays (yes it sure looked like it before the DLC) it just destroys all synthetic life. So reapers, Geth, EDI, and anyone else who is implanted with enough tech like Shepard. And that is why I had such a problem with that ending, I could understand Shepard dying (still think there should be a way for him/her to live on with their love interest) but I should not have had to wipe out the Geth who I had just got to work together with the Quarians, not to mention killing EDI just sucks.
But rest assured the modding community can come to the rescue. There is now a "happy ending" mod. I have not played it yet but it seems to get good reviews and will be giving it a go once I get that far again. Here is a link to it:
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