I love browsing Mens websites... nothing like getting a little insider information...
This comes from askmen.com, I found it interesting and for me pretty accurate... what do you think?
Number 10 Letting things go
One of the most common ways guys blow it is by letting standards slide. You made all the effort to get the girl, then you took your eyes off the game. Now that all the hard work's over, it's OK to put on a little extra weight, right? Maybe you don't make as much effort with nice clothes because you don't have to impress her any more. Well, you're wrong. This kind of behavior sends out the message that you think she has low standards -- and she will not be happy about that. Keep on top of things and make sure you look like the kind of guy she should be with, instead of falling into one of the ways guys blow it in relationships.
Number 9 Playing a character
If your relationship is going anywhere, you have to be yourself. When you're first getting to know someone, it's tempting to say what you think they want to hear, just to make things run a little smoother. Trying to impress her by faking or exaggerating parts of your life and personality might reap short-term rewards, but eventually it'll all come crashing down around you, which is why this is precisely one of the ways guys blow it. Sure, make your job sound a little more interesting than it is -- that's fine. However, pretending you're a high-flying entrepreneur to impress your girl just isn't right.
Number 8 Being stuck in the past
As the old expression goes, pasts are like assholes: everybody has one and it usually stinks. Up to now, every relationship you've had has failed. From broken hearts to broken egos, you've done it all. However, that was then and this is now. Leave the past where it belongs and start working on the future before you succumb to one of the biggest ways guys blow it. The same goes for her past. Don't judge her by what she's already done or try to keep up with the wild times she's had. Keep your pasts as memories and start making some new memories together.
Number 7 Too serious, too fast
You like her. You really, really like her. It's only been a few weeks, but you think you should call and say you love her. You also think you should call her more than once -- just so she gets the message. Maybe you even want to move in together. Why not take some of your stuff over to her place, right this second? On the way, there's that nice little jewelry store, go pick up a ring. If you start organizing it now, you could be down the aisle in no time at all and have the perfect summer wedding -- and then children! Has she thought of any names yet, because we bet you have? I think you understand why this approach is one of the sure-fire ways guys blow it.
Number 6 Persisting in playing dating games
The old story of boy-meets-girl, they like each other and live happily ever after just doesn't work today. Somewhere along the line, dating got a whole lot more complicated. However, one of the biggest ways guys blow it is by playing dating games that eventually blow the whole relationship out of the water. Sure, curbing your enthusiasm is a good thing, however, waiting a week to call, canceling and rescheduling dates, and generally playing hard to get can often cause just as many problems. Believe us, enough of this behavior will have her bored at waiting around, and that's when someone with a more direct approach just sweeps right in and steals her away.