Desperate for advice

Hey ladies I need your help.

I just recently got engaged to the man of my dreams, I really do love him so much but for some reason I'm so mean to him :( I don't mean to be but I just cannot speak nicely to him. I am really worried that I may have a mood or personality disorder. Has anyone else ever exerianced this? If so what helps?? I am currently looking into therapy. I dont want to ruin my relationship