I do, after running across some info today, even more strongly now, believe, that she and the sisters, were victims of abuse as children. I wasn't sleuthing the extended family, but an article I read, while looking for info on the T parents, led me to kinda believe that LT isn't the only sister who has lived like this. I think those girls may have had a rather difficult time as youths. You can tell something is just kinda, well, it's in the eyes. Maybe she saw DT as her savior. The knight in shining armor that would take her way. If they just wanted to split and get married, they could have done that in TN. I can't post the article b/c TOS.
I do not however, see her as a victim, in her marriage to DT. I see them equally at fault. Although I do think that she has some type of mental health issue. That doesn't mean that she doesn't understand right from wrong, or that DT couldn't have sought out help for her.