A glass container can only stand so much pressure from its contents.
If it is over loaded it will crack and be destroyed.
We are glass containers and what God gives us is according to our capacities.
If He gave more we would break.
He never gives us more than we can bear even though we may genuinely perceive it that way.
His Mercy itself is unlimited and we ourselves are the limited.
So any limitation of His mercy we perceive is only due to the limitedness of our containers.
May He continue to have Unlimited Mercy despite our limitations and may we continue to rely on Him to accept it, inshallah. Amin