Jamie Lynn Spears's fiancé Casey Aldridge is getting ‘cold feet.’

“Casey is not happy right now. He feels trapped. He’s just miserable,” says an insider.

A friend of Aldridge reveals that he feels he is being forced to marry Spears, 17, since she gave birth to their daughter Maddie in June. “He was told it’s the right thing to do. But it’s not the life he pictured for himself,” the pal says. “He feels his life is over. He had things he wanted to do, but now he can’t. He’s fed up. It’s like he’s got the whole world on his shoulders.”

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