Ask HN: How often startups get acquired and you get nothing?

Today the startup I worked for got bought out. I am one of the first few Developers with employee stock options. I have given 3 years of my life to this startup. I believed in what we were doing. During this time I have seen one complete product rewrite, Whole top management being replaced (CEO, CTO, etc), numerous product direction changes. I worked on some of the most critical pieces of the software. I lead the last rewrite as the Principal Architect (with very high control on what to be build). This last rewrite lead the startup being bought out by a very large enterprise company. In the end I got nothing. They tell me my stock options are worth nothing. This has happen to me second time. How often this happen? Is this normal? I am frustrated. The only solace is that they are keeping my team so at least i know my team has a good home. I have decide not to be part of this acquisition. I am Frustrated and not sure what to do next. PS: It was a Venture Capital backed startup