80's R&B song lyrics search

i don't know the artiste but here are the some of the words to the song...the chorus is pretty much accurate...please help i have been searching for this song on and off for 15 years

the first time that i saw you, i was go-ing out with my girlfrieeend,
i put her doown (backup singers...i broke her heart for you)
now i'm paying for that mistaaaake


the chorus goes something like this
so hard living with you, i know, i really tried,
gonna be so hard, so hard living without you, but i know, i will get by

it's so hard, so hard, loooooving you,but i know i really tried
gonna be so hard, loving without you, but i know i will get by,

last verse is like this

and sweeeeeeetheart, though i still really love you (backup ...i- can never be yours again)
you did me wrong, (back up...don't ask me where i've been)
cause you don't have the right anymooore

I too remembered this song and searched to find it as it remained in my head since the 1980’s. I decided to do a quick search tonite on a whim having finished some writing. I have searched many, many, many times before. I typed in the main lyric so hard living with you and it was there with other songs on youtube. I had never seen the group before (the others I had checked before)and it was near the top. I listened and there it was ….those lyrics! May it bring you joy my friend and don’t forget to vote Nov 4th Lee
Windjammer - So Hard
Youtube https://www.youtube.com/watch?v=uf8q7HNbJGY
http://youtu.be/uf8q7HNbJGY