I’m paranoid that my girlfriend lies to me to make me happy

This kind of paranoia is what could make you lose what could be the best thing that’s happened to you up to now. Maybe you ARE all that. At least she seems to think so. Try to appreciate it.

Everything is roses in the beginning. Give it time. True nature will reveal itself

As Lestat565 mentioned - we tend to lie to those we care about in order to spare their feelings. So it is kind of funny - we do something "bad" with good intentions.

Now in your case, she is probably not lying. There are a couple reasons -

1) If there were a problem, she would not hide it from you. Women are very good at finding and pointing out faults in their partners.

2) As Whatintarnation said, everything is roses in the beginning. Even a person's flaws or bad habits seem cute at first. You like everything about the person. But as time goes on, you start to get annoyed with the other's flaws, bad habits, etc.

So for now, just enjoy how things are. Try not to read too deep in it.

Of course she lies to you. Everybody lies including you. You can’t tell me that you haven’t lied to her before because you cared about her feelings. We tend to lie more to those we care for than those we don’t. And I’m someone who hates lies. I believe that one lie makes every truth look like a lie. But I have still lied in the past and likely will in the future. Everyone lies.

Why would she?

Paranoia is bad.