Ask 1 of your Bros to borrow theirs..
Nothing is free. You'd still have to come up with money for insurance, fuel, & maintenance. Riding is a privilege. With PTSD I'm not sure owning a motorcycle is your best solution. If you want to try riding maybe borrow a friends bike. Depending on your PTSD & mental status - riding may not be the solution it may actually exacerbate your issues.
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