Thanks for the Memories

I've written this poem for my friends.. We are in our last year of "high school"(not quite the same in the Netherlands) and our ways are gonna split.
I want this poem to be perfect, so please be honest
(I know my grammar is bad, so if you could help me with that?)
thanks!!

They say that nothing last forever
Well, I think that isn't true
Because the things that last forever
Are the memories of you

Memories of a year
Which could never last to long
Because we've build a friendship
So powerful and strong

Memories of people
Who are different like day and night
And though we sometimes like to tease
There's always respect from each side

Memories of crazy times
I think I've never laughed this much
And when you feel down there's always
Someone with a sweet word and touch

Words can't possibly write down
How much those memories mean to me
When I think of our friendship
I realize I can't be more happy

And though it's time to move on
Different directions, different ways
We stay forever bounded by our memories
Of all those beautiful days