What is this song?!?!?
 

I am getting frustrated on this song I can't find. I know some lyrics and I think it's the hook too use every search site and even sung it myself for it to find it and nothing can anybody help me it goes like this
"It's so harrddddd to love someoneeeeee, it's just your illusion that is stuck in my heart. (Stuck in my heart)"
I don't know if that is the right lyrics but it should be pretty close :-(
And I am positive it is either R&B or pop