I wouldn't say a 'clingy' partner is a perfect partner.

By acting the way you are she's more likely to do something to make you paranoid. So you've either got to chill out and give her space, or realise that you're not compatable.

If you stop being so full on she may well miss the attention, and end up being more attentive, which in turn will make you more trusting, and hey presto - relationship fixed

But seriously, sometimes people can be together for the wrong reasons, and the relationship slowly declines until you reach a point when you wonder why the fuck you've wasted so much of your life with her.