Whats the biggest losing trade you ever had. I think mine was losing $50,000 on a Dax trade, back in 2013, was long time ago i. dont remember the details. I might have lost more once on a trade in ZN during NFP back in 2009. Not quite sure.
Don't care that much. Just last week, I had ~$9,000 of surprise expenses related to site work on a property I'm building on. It's not much different than that. I'd rather it not happen again obviously.
If the OP is real, I think he needs to research contango. I don't know why you would ever hold oil futures for several months. You'll get absolutely killed by contango, especially in this environment. I don't get whats so bad with trading oil contracts 6 months out, personally, although maybe a bit odd. I understand why you wouldn't want to do it, but I missing why it's that bad of a decision. Before he did the math on what each tick costs and decided to exit quickly, it sounds like the OP was going to buy and hold for several months where liquidity wasn't an issue.