I'm a 30 years old and after a lot of attempts at relationships with guys and girls I find that I'd rather be single (90% of the time) but still want a relationship (10% of the time). Is that strange? Or am I just having a midlife crisis?

You will go through all different kinds of situations as you get older. When I turned 50, I thought the world had come to an end and started dating after being single for many, many years.

Now that I'm looking at 60, I don't care any longer. I strive to be happy in who I am and that's enough for me right now. Who knows what I will feel in 2, 5, or 10 years from now? I surely don't.

My advice - be happy in whatever stage of life you are in right now. If you are unhappy, then you need to puzzle through why you are dissatisfied so that you can improve it. Good luck!

You just haven't met the right person for you yet and are looking for logical reasons.  Just live your life and don't try to analyze things like this.  Find your own personal happiness independent on having someone else in your life all the time.  You'll be more "attractive" that way and make better choices too.

No its not strange.