"Thanks to everyone for all the support through a very difficult time!" he Tweeted on Saturday.
It was only his second Tweet since March 18 – then in the midst of reports that LeAnn was conducting an alleged affair with actor Eddie Cibrian – when Dean Tweeted simply, "I love my wife!!!"
The account has not been officially verified by Twitter.
On Friday, a source told People that the couple had been "separated for quite some time now, but they continue to try and work through their relationship."
The two married in 2002, but earned headlines earlier this year after Us Weekly alleged that LeAnn was seeing Eddie, who co-starred with her in the Lifetime movie "Northern Lights." Eddie and his wife, Brandi, reportedly announced their own separation earlier this week.
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