Why does the hills always make it seem like Heidi and Spencer have relationship problems?

I feel like it's staged. First off, the people who know them say that he adores her but on the show it always appears as if they are fighting or having some problems. Last season it was Stacy the bar tender, but now she's friends with them and was at their wedding? The new season preview shows her trying to rush to have children and him being all upset about it, but in real life-interviews he said that he couldn't wait to start a family with her. It all seems very fake.