After reading the following, BBM:
"[Arias] was totally obsessed with him," Hughes said. "She wouldn't let him go. Whenever he would try to sever all ties, she would threaten to kill herself ... He would tell her he didn't want anything to do with her, and she would show up at his house. We knew it was her. We didn't want it to be her, but [we] just knew it was."
http://www.huffingtonpost.com/2011/12/29/jodi-arias_n_1174274.html
I cant help but wonder if that last eerie photo of TA in the shower was when TA saw JA with the knife/gun pointed at herself as a fake sign of impending suicide.
Could JA have subsequently dropped the camera as TA lunged toward her in his attempt to disarm her from hurting herself and JA intentionally and premeditatedly turned the knife/gun on TA?