First: Break it all down, go through: risk vs. reward, cost analysis, schedule impacts, steps, etc.
Second: Having a plan B or backup plan is essential. (even though you always plan for success and not failure).
Third: Make a decision and be willing to stick with it if you truly believe it's the right one. You will do whatever it takes to make it successful.
Why wasn't I able to do the same with my current decision? One of the things that affected my decision was all the personal factors causing changes to my original decision. In turn, led to frustration, stress and uncertainty.
So a lessons learned for me is yes, it's ok to change your mind. However, once you have decided, don't second guess yourself. Instead embrace, enjoy and run with it. The decision might not be easy, but in the end, it's your decision.