You are scared to love her and want out, but it's too late. You DO love her for everything you can have from T and everything she can provide. I know thinking of loss feels overwhelming and huge especially given your H passing away but you are not being asked to tackle it now. Future Rainbow will have to contend with and I don't know how independent she will be, how prepared she will be. You are not the same person you were a year a go and nor are you the same person you will be a year from now. Try not to panic over future potential problems. You have a good thing and you don't have to push it away. You deserve to enjoy the good thing. Don't sabotage it.

Love isn't a choice and you already love her, you may as well embrace it an enjoy it.