Who is she?

My ex just texted me after no contact for a year last night and idfk what to think about it apparently they were in the mental hospital twice and they were through a lot I don't know whether to believe them or not I mean they have no reason to lie it's not like our relationship was that special back then but it's so confusing I think I might actually believe them because it feels like they're a different person my brain feels so confused or whatever they don't remember much about me I told them about how they cheated on me twice and they didn't remember it but they felt bad about it I told them it was alright and that was in the past now but they insisted that I forgive them