Prosecutors believe Middleton married the women so he could access their money, New Hampshire Public Radio reported.
Grant reportedly became suspicious of Middleton when she called him and another woman answered his phone, claiming to be his wife, the Union Leader reported. She then called police, who began investigating her husband.
Sheriff's deputies in Franklin, Ohio, arrested Middleton in February after he missed an arraignment in New Hampshire. In a tweet about his arrest, officials called him the "Cupid of Chaos."
>> See the tweet here
Authorities in Maine also have charged Middleton with domestic violence, according to The Associated Press.
During Middleton's sentencing Monday, prosecutors read a statement from Grant, who said her life took a dark turn after she married him.
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"When we got married six years ago, what I thought I had found in him was a life partner, someone that I could face life's ups and downs with, someone my children could look up to," her statement read. "Instead I got six years of pain and misery as I tried to free myself from the prison of his lies and manipulations."
New Hampshire Superior Court Judge Steven Houran issued a 12-month suspended sentenced for Middleton, who "will avoid jail time if he remains on good behavior for the next five years," the AP reported. He also must complete mental health, drug and domestic violence screenings, according to the Union Leader.
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