The Loose Women presenter's ordeal began after the man - an acquaintance of her second husband - offered to help with house renovations and swapped business cards at a social event.
© Rex Features / Steve Meddle
McLean, who recently split with Steve Toms, has been "feeling ill" with fear over the stalker, reports The Mirror.
"The man seemed to think because she was newly single she would fall at his feet because she was vulnerable, but the messages made her skin crawl," a source told the paper.
"She knew the man was married so would never have got involved with him. The guy was a real creep."
The insider added: "Andrea ignored the messages at first, but they continued for some time until she felt she had to do something about it."
The 42-year-old has apparently been receiving the messages since January, when she took a break from Loose Women due to her marriage break-up.
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