Should I leave or try to fix what we had?

My family has gone through a lot lately with three separate deaths and my grandfather not doing so well in the last few months. My partner of 3 years told me that he needed a break and left. That was only 3 weeks ago but this weekend, he reached out saying it was a mistake. 3 weeks isn't a long time but having him leave at all was so devastating and I'm still incredibly hurt by the whole thing. I've missed his support and his love and his help. Ive missed the big aspects of having him in my life (having a partner to share the good and the bad) and I missed the little things (sharing our day with each other, giving each other long hugs after hard days).

I dont know if i should try to make this work or tell him to leave me alone. I've heard some people say that I shouldnt take him back because his decision to leave proves that he isn't a trustworthy partner. And others have said that he has been a great partner up until this point and this is the type of bump a lot of couples face. Am I giving up too easily on something that's fixable if I walk away? Or am I fooling myself that this can work after he left when I needed him so badly?

I've been debating what to do for the last few days since he first reached out. I dont think I'm any closer to deciding. But now my grandfather is doing even worse and I have family rushing over to see him right now to see if he's ok. All I want is to do in this moment is text my ex so he can calm me down like hes done before when I'm overwhelmed.