Thomas Markle Jr, 53, has fallen on hard times after losing jobs and splitting with his fiancee.
He revealed he has been forced to move in with his elderly mother in New Mexico after his life “fell apart”, The Sun reports.
Tom — son of Meghan’s dad Thomas Senior, 75 — says he has lost out on jobs because of his name.
The glazier also said he has suffered from depression and is considering changing his name to escape the “curse”.
He added: “Being associated with Meghan has nearly destroyed me.
“I am homeless and could have been under a bridge with a cardboard sign begging for money.
“But thankfully my Mom has taken me in.
“Mentally, this has been a f***ing nightmare ever since Meghan got together with Harry.”
He said his sister could have helped him out or got the Palace to do so.
He added: “For her to sit there on her royal pedestal and watch this happening to her family — she should have done her humanitarian work for us.
“I’m sick of hearing about her and Harry helping this charity, that charity — whatever cause is in this week.”
Markle Jr was arrested in Oregon last year on a drink-driving charge. In 2017, he was arrested following a drunken row with his then-girlfriend.