No need to be sorry for loving 28mm. (unless you mean sorry that the 1.4 does not exist)
It is all up to your shooting style.
If you are shooting crop, then Sigma is there for , as already mentioned.
But for FF, I guess you have to put your hopes to Tamron, that have said they will go for fast primes next.
If you have a NEX, you could try the EF50/1.8 or EF28/2.8 with Metabones adapter?