What do you want to prove?
It's not so much about what is there–the evidence that can back up your pre-emptive conclusion–but what you look for. Are you trying to inspire yourself and be hopeful, or are you trying to scare yourself away from doing something? There's always some on both sides, and it's always easier to find what you're looking for.
When it comes to making big life choices, you'll never have one that is an obvious decision. There will be fear, as well as promise, and risk, as well as reward. But you can cut through the muck by asking yourself this question: What am I really trying to prove? Answer it with honesty. You might be trying to prove that you don't want to do something because it's unknown and scary, or you might be trying to prove that you don't believe in the other person's motive. Truthfully answering this question will let you know a lot about your current state of mind–and how much you really like (or not) the truth that's right there in front of you.
You are the attorney, judge, and jury of your life, i.e. you are Judge Dredd.
If you want, you can poke holes into anything, and argue it down to submission. And if you want, you can be that same thing's biggest chearleader, and find the positive lining to everything.
Whatever case you make will win.