Agreed. The drinking and smoking was a big "F-you" to somebody, either Daniel or her brother or both. I don't think she meant to kill herself and the kids, but I think when she woke up with a hangover and realized she had to have her nieces home by a specific time and Danny wasn't going to help her, she was pissed off at everyone and was going to "show them" by turning up drunk to drop the girls off.
I would agree with the first sentence.
I have read many of the suicide theories. Only one of them kind of strikes me as semi plausible. I can't remember who posted it, but it comes down to:
DS didn't leave camp intending to do anything other than take the girls home. Something happened in the interim which resulted in the drinking and smoking, most likely her being extremely upset at someone or about something. Maybe hungover and attempting to take the edge off and ending up going off the rails, whatever. At some point one of her nieces calls her Mom, CRYING, saying "something's wrong with Aunt Diane." Jackie can hear one of her other daughters crying as well. Naturally alarmed, she asks to speak to Diane, who denies anything is wrong and tells Jackie the girls "are playing, and having fun." Jackie knows that cannot be true if two of her girls are upset and crying. Additionally, Jackie's impression is that Diane "is not making any sense."
Warren gets involved and orders (or begs) Diane to stay put and wait for him. She leaves her phone at that spot and takes off in the exact opposite direction he would be looking for her. At this point it may be clear to Diane that all of the years she has spent trying to make others (and possibly herself) believe that she has it all together both personally and professionally are about to come to a horrible, humiliating end. Either Warren meets her at the bridge and realizes she is drunk, or she delivers the girls to his home and it's evident that she is drunk. Either way, her image comes crashing down all around her and she is revealed to be imperfect, and quite possibly she is revealed to have a substance abuse problem she has taken great pains to conceal. Perhaps she cannot face those outcomes. She decides to commit suicide and the children are, quite simply, regrettably but unavoidably collateral damage.
Perhaps she merely intended to flee and kill some time until she could gather her wits about her and come up with a plausible story to explain her actions. I could well believe that too.
But toothaches, strokes, poisoning by fast food employees, laced marijuana, etc., no, just not plausible imo.
She screwed up-like many, many, many mothers before her have done.
