My mother's remarriage: My mother married my best friend

It happened suddenly... my mother married my best friend. When I first heard it, I couldn't hide my confusion. However, as I saw my mother's happy appearance, I couldn't say anything. My mother raised me on her own after I divorced my dad. No matter how painful and difficult it was, he always smiled at me. If that mother would make her laugh out of her heart by marrying my best friend, then that would be fine...