HumSafar Song Lyrics in Urdu:
Tark-e-taluqat pe roya na tu na main,
Lekin ye kya ke chain se soya na tu na main.
Woh humsafar tha magar us say humnawaayi na thi ,
Keh dhoop chayon ka alam raha, judaayi na thi.
Adawatain theen, taghaful tha, ranjishain theen magar,
Bicharne walay mai sab kuch tha, bewafayi na thi.
Bichartay waqt bhi un aankhon mai thi humari ghazal,
Ghazal bhi woh jo kisi ko kabhi sunayi na thi
Okay i found this translation, the credit goes to the translator !
(These are the main lyrics, they are just repeated in the song)

HumSafar Song English Translation:
When we parted ways,
Neither you cried nor I,
But, what is this,
peaceful sleep since,
Has not touched our eyes?
He was [bad word] 
But not in harmony were we,
Like the clouds and sunlight,
Together but as apart as can be.
There were feelings of animosity,
Indifference,
And anguish between us,
My departed lover, had been everything,
But unfaithful.
Last time I looked into his eyes,
My poetry reflected back at me,
Verses, that which I had never,
Recited to anyone.