Answer: I had been very selfish.

How selfish I have been from this statement?

Answer: Winter made him realize his mistake. Once he found the spring has arrived in his garden with children playing happily,he realized that it was his selfish behaviour which kept his garden covered with snow . ... The little boy kissed him in return which made him feel happy and changed his behaviour.

How selfish am I in my grief make assertive?

Since the given sentence is positive so its conversion is in the positive assertion. Hence the sentence changes to, 'I am selfish in my grief. '