Losing Google would see a big revenue crash, but enough would still be coming in to regroup and rebuild without any unplanned restructuring.
In my case, as it is with a lot of others is that I was, through google, able to obtain enough work. To explore other avenues would have meant potentiually more work and I was sometimes struggling with what I was getting. I was at that cusp in my business, either to grow with the work and take on more staff or just continue with it as it was. I do have other avenues open to me but they are very narrow at the moment. I wrongly thought that if I ploughed all that I could back into my website and made it better and better that google would reward. Not the case. What they like is crappy copycat link spamming sites. Google likes spam. They help produce it and promote it with adwords and adsense and by rewarding spam in the organic SERPS.