Nolan Wells' Mom Reveals Hate Mail Amid Push for Answers in Son's Death

Nolan Wells' grieving mother says someone sent a cruel piece of hate mail straight to her home ... mocking her push for answers about her 18-year-old son's mysterious death.

Christine Wonsley shared the anonymous mailing on Facebook ... a photo showing Rev. Al Sharpton and attorney Ben Crump supporting her alongside her husband, Elmore Wonsley -- now defaced with arrows pointing from the men toward Christine and dollar signs seemingly implying they were exploiting her grief for money.

Christine fired back, writing ... "Whoever sent this to my home, may the good Lord have mercy on your soul."

She called out the sender for being bold enough to mail the "crap," but too cowardly to include a return address ... adding she and Elmore are grieving parents who merely asked what happened to their son and accepted help finding answers.

Her message to the anonymous troll was blunt ... "Please go touch some grass."

As TMZ previously reported ... Nolan disappeared during a Fourth of July boat trip to Mississippi's Horn Island, where his friends said he stayed behind without his phone -- his body was found in the water two days later.

Authorities said they believe he drowned and detectives had not uncovered evidence of a crime ... but his family has questioned that theory and launched an independent investigation with Crump's help.