The fact that dragons become living corpses after their mates die and the fact that he didnt even know/think she was his mate not until she took her life means that he only turned back time because he was going mad at being mate-less, not because he actually cared for her or felt sorry for her. It's as if he only "loves" her and wants her alive because he needs her for him to stay sane.
I'm sure this is opposite to what the author intends to show, but ml's feelings are so fucking shallow. He doesn't need Solan the person, he just needs the role Solan plays as his mate.