Figured it out a while ago.
Ruth regrets it, but sent faith back to " make amends" I think the death with his baby is why and what he thinks faith betrayed him. The first round, of her going back she was scared and confused. Held a fear for him, because she fears future Ares, she gets rid of the baby, fearing the vampire, confusion being scared inc, is why the first round failed, because I think the first run was ruth sending her back because she regretted staking him. After finding out that cyrus was evil. Shes remembering the first time she went back. Because then she didn't know much about him. It failed because while she had fallen for him, she still feared him. She have the cross she gave to ruth , which reset the time line. If faith gives ruth the cross they can reset the time line indefinitely. The second go around, Ruth's soul remembered and was all ready in love with him. Making her his beloved, this time line he was turned to stone. Instead of staked because she made a deal with ruth. Weather or not the timeline the key factor in his betrayal is her ending there baby. Her amends is deciding to keep it. And this time telling ares of why she is here and the deal she made. Shes his beloved, because her soul recognized his soul who had fallen for her. This time she decides to keep the little one and get some of his blood for ruth. Because as I see it, shes basically rewriting history as she moved forward.
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