Peony Advice?

Hey everyone! Spring has sprung here in Philly! The temps bounced up to 82 on Monday and are expected to plunge to the low 50's on Wednesday! Stay tuned...

The most important peony in my yard is the weakest, can you help?

Ma gave me this division from her plant and I believe this will be the third season. It was originally from my

G-Mom-B's yard and it's very important to me that it be healthy and happy!
Obviously it is not. 

While all of the other peonies have sturdy 1/4 to 1/2 inch stems, 

this one is only about 2 millimeters. 

It hasn't bloomed and simply died back with the awful hot/no rain summer we had last year.

I don't know it's name but the flowers are a very pale pink that fade to a creamy white. 

My questions to you: 

Do you think I planted it too deep?

This is against the back of the house and does get full southern exposure sun, maybe it needs more shade?

Maybe it just requires more time to get established and this Philly girl needs to relax a little?

Any other thoughts?

Thanks and have a happy day:@)

I'm joining:
Nifty Thrifty Tuesday - third generation family transplant
Fertilizer Friday - it's not blooming but it's up and I haven't participated in FF since July!