One of the things that really messes with me is the pressure, both from within and from outside myself, to be perfect. To name a few: I must earn good grades, find a well-paying and interesting job, write flawlessly, perform brilliantly in all social interactions, never let anyone down and always be happy.
Right.
And I know it happens to you, too. This is one of the most destructive lies we tell ourselves. Because we will either be constantly stressed and under pressure to achieve, or we will become consumed by whatever ways (real or perceived) we may fail.
As I said, these expectations can come from two sources: myself and others. In most cases, though, the pressure from others is really coming from me, too.
If you find yourself feeling constantly under pressure from others to be perfect, examine yourself first. Are those expectations really coming from someone else? Or are they projections onto others of your own expectations? Do you expect that they'll have expectations, and therefore bury yourself under pressure they may not even be exerting?
If, though, the pressure really is coming from someone else (family is generally the biggest culprit in this, particularly parents), you can--and, really, need to--work on adjusting those relationships. Talk to your parents and tell them you feel overwhelmed by how much they expect from you. Tell your friend that you do care about them, but you can't constantly be everything to them. If you're lucky enough to have a healthy working environment, talk to your boss about what's realistic and what's fantasy in terms of production. You can't always fix things, and sometimes relationships need to be sidelined if they are having a toxic effect on you. But you should certainly try.
If it turns out the pressure is all from yourself, well, that's harder. You have to live in your head 24/7. But you have to learn to let go. Set realistic goals. Have a reward system for achieving them. Don't expect to be perfect, and don't hate yourself when you aren't. No one else does. Love yourself for the skills and abilities you have. Be thankful for what you have and where you are, for what you can do and the difference you can make. And when you mess up, forgive yourself and learn to move forward to the next thing.
Because idealism (that is, expecting the ideal) is paralyzing. How many people never start something because the idea isn't ever quite good enough? It could be a project, a relationship, a business. I've done it, with all of those. If I don't start, I can't fail, right? But that's the thing: almost every good thing you can do/have/learn/experience requires risk. Yeah, I might fail. But what about what I might achieve? If I never start, I'll never know. Is that really worth the "comfort" of playing it safe?
No, it's really not. Think about the things in your life you wouldn't have if you'd always taken the easy road. Let them encourage you to go and do, to risk and be free.
So expect yourself to be good. Expect yourself to do your best. Do what you can. But don't expect yourself to be perfect.