I'm really new to songwriting. i have came up with a bit and would like to see how you guys think of it so far, if I should keep it or trash it.

As I stepped onto a sidewalk, on a lonely Friday night
I know if it was not for you, I would be home tonight
You know all the reasons, the reasons I am wrong.
You’d place the blame on anyone, just to see them gone

To me I feel it sounds pretty well, I just don't know how to come up with a melody to sing it in. Every time I read it I always start thinking of a melody from some other song, same thing happens with everything I write. Is it bad if other songs get stuck in my head while im writing it?
what i recommend is playing it as the song you get the melody from, and then tweak it until it doesnt sound so much like it anymore.
hope that helped.

as for the song, is a good start, but you need some more. maybe explain it a bit.

check out mine if you ever get the time.
its called "Dear Penthouse Forum"