Coruscant was not destroyed
The planets that were destroyed were Hosnian Prime and four other unnamed planets in the Hosnian system.
From the Alan Dean Foster novelization:
"General, the Republic Command — the entire Hosnian system — it's all...gone."
"Until the Hosnian system was eliminated, we didn't even know such a weapon existed."
So, there's no deal to be made concerning Coruscant.
Reaction to Hosnian massacre
As for the reaction to the destruction of Hosnian Prime and the other Hosnian planets, I feel it is necessary to point out that The Force Awakens takes place over the course of only a few days, and that the Resistance is very preoccupied during that time — especially after the destruction of the Hosnian system. We don't really have enough time to see or gauge any general reaction. Quite literally, the dust has not settled yet.
That being said, the novelization gives us some insight into Leia's feelings on the massacre:
First Alderaan, now the Hosnian system. No one, she knew, should have to be witness to the death of an entire world. She had been subjected to two. It must not be allowed to happen again.
Her feelings are likely echoed throughout the Resistance.