It's true. When you want to learn a language similar to your own, it conflicts with your instincts. It messes with your head. It makes it harder when someone else thinks it would make it easier.
But like I said, it's mostly grammar that just sounds wrong but sometimes the meaning of words too. When I learned French, it was so easy. You start from scratch and everything is new. Perfect example is this:
'naar' in Dutch means being rude, in Afrikaans means feeling nauseous
'misselijk' in Dutch means feeling nauseous, in Afrikaans it means being rude
That plus the spelling of certain words which just looks wrong, causes you to make mistakes an Italian learning Afrikaans wouldn't make