Mail Order Melancholy. Brides of Beckham, #25

Gretchen Jensen has been in love with the same person for years. There are only two problems standing in the way of her marriage to him. She's pregnant, and he's dead. Most of the people in her town won't even talk to her, because the woman who was to be her mother-in-law has shunned her. Unable to see beyond her love for him, she refuses to marry the mail order groom who has traveled across the country to be her husband.
Reginald Lindon left town at a moment's notice, but he took time to leave his fiancée a letter to let her know that he would return in six months. He entrusted his mother to give the note to Gretchen so she wouldn't worry about him. When he returns to town, he realizes everyone thinks he's dead. Gretchen claims his mother never gave her the letter, but his mother claimed she got it and said he was dead to her.
How can he know who is telling the truth? And will they be able to get past this rocky time and trust one another again?