Le Couple (ル・クプル)'s ひだまりの詩

I used to listen to this song and sing along with it without knowing its meaning. With my lousy Japanese, I still could not understand its meaning and googled for the lyrics meaning and found this link with the following translation:

How long has it been since I last saw you?
This morning, the letter I sent to you was sent back
Like the newly awakened leaves waving by my window
Only now I've realized that the long winter is past

No matter what I say, it's just no use
You loved me, and embraced me completely
You were like the warmth in my life

In our last photograph together, the flowers are ablaze
And yet I can't keep my promise to send it to you
Even if now I were to receive
Both your kindness and your stubborness

Even if I were to grow to like other people
I'll never forget all you left for me
So that I could love again
Even if I never see you again in this world, I'll go on living
You loved me, and embraced me completely
With all your heart
You were like the warmth in my life
You loved me, and embraced me completely
That was the warmth in my life