Marshall told the South Florida Sun Sentinel he needed help in getting a handle on the disorder and is ready to pay it back.
"Before this ordeal I kept asking God to show me my purpose and he gave me this," Marshall said. "I'll be the face of BPD. I'll make myself vulnerable if it saves someone's life because I know what I went through this summer helped save mine."
What Marshall went through during the offseason was a three-month stint at McClean Hospital, a Boston facility used to train Harvard Medical School students.
A battery of psychological and neurological tests left Marshall with a detailed awareness of his condition and tools he says will help keep him on an even keel. "By no means am I all healed or fixed, but it's like a light bulbs been turned on in my dark room," he said.
BPD is noted for emotional outbursts of the type that marred his college and pro career. Things reached a low point this spring when his wife allegedly stabbed him in the leg during a particularly heated row at their Florida home.
"BPD is a well understood psychological disorder," Harvard psychology professor Mary Zanarini told the Sun Sentinel. "It's not a form of misbehavior."