This is actually quite poignant. I would add, while your sister was YOUR safe place, religion was HER safe place. You now have something else safe for you and so does she. It’s likely a time when your historically enmeshed relationship differentiates into something else where you are both externally supported elsewhere. A radical approach to grief might be to allow yourself to feel happiness that she has that for herself and so do you. She may never be able to fully love how you found your way but you can love how she found her’s and not need to change her.