Last year the amount of money spent on healthcare (not on health insurance, but on actual treatment like doctor visits, medication etc) hit a 10 year high. They believe much of that is due to all the people who now have health insurance that didn't before (meaning many of them that are on medicaid etc) actually going to the doctor and buying the medication they need.
When more people buy healthcare the cost of insurance goes up.
Health insurance rates have been rising for 20+ years. They may have taken a slightly larger turn in recent years, but look at
this page and see how from 2004-2006 the average person saw their insurance premiums rise 8.8% per year. In my state premium costs went up nearly 20% during that time period. This was long before there was Obamacare. Where was the outrage?
Bash him all you want, Obamacare isn't great and it has some fatal flaws, but our system was headed for bankruptcy long before it came into being.