That was an interesting question. I am in my Chariot year now, but I really had to stop and think about that.
Here are my thoughts. The Chariot to me is a card that normally says that willpower and self-control are needed in the situation. And that if you use these tools properly you will come out of the situation victoriously. Boy does that EVER describe the year I am in now too!
Ok as for the question: "What do I need to let go of in my life?" If the Chariot is about self-control, always needing and trying to control yourself and your life, I would think that the answer to your question is that you need to work on letting go of your need to always be in perfect control of yourself and your life, that you need to work more on just relaxing and going with the flow, and that you need to work on trusting that your life and the universe have your best interests at heart and will take you towards your best future even if you let go and trust.
Just let it go more and more, the need to be in perfect control of your life/yourself and just flow with life and trust that your higher powers will take you where you need to go. Perhaps needing to be in control at all times is stressing to you, as no one can be of course. The card to me is telling you no one can be in perfect control at all times and that's alright. You can just accept that and know that you're safe and that at those times when you are not in complete control there is a higher power that is.
...just my thoughts...
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