People in AA don't shoot their wounded because we have all been there. Some of us did all of relapsing before coming into AA. Some of us relapse after coming to AA. I don't know of anyone who quit drinking for good on their first attempt at it. I certainly don't believe relapse is a necessary evil, just an evil that does exist in reality. Use it as a learning tool.
Have you ever watched a baby learning to walk? A quick butt plop is the usual result. The baby does't beat itself up wondering if he is going to lose his friends and respect. He merely rolls over on all fours and gets back to it. He looks to a brighter future and mastering this skill that will open new worlds.