You've addressed several concerns clover4you, making any solution no simple matter. And though the comments above offer some good support and advice, allow me to add a different perspective.
As a critical person myself, I am sometimes accused of being a negative person simply because I notice and make comment on the stupid or wrong things I see going on around me each day. This was enhanced with my careers as an inspector and law enforcement officer, where I was paid to find and address problems. And it continues now as I travel the world full time, dealing with incompetance, mistakes, and frustrations daily, while witnessing an amazing number of stupid people and 3rd world cultural attitudes that truly test my patience. The fact is, that people and the world around us are full of annoying flaws, and little things seem to go wrong all the time. I'm sure that some of us are more perceptive of this than others, but I don't think that being attuned to people and things around us is wrong. What we think and how we respond is of course the relevant concern.
While some of us may never be able to ignore the many flawed people and things around us, there are a couple of things that can help us respond better as we do encounter them: balance and perspective.
By balance, I mean being as critically observant about the positive things around us as the negatives. I can confidently say that, even in the dirty, messed up environments that I live in overseas, the number of attractive, neat, interesting, amusing, or entertaining things around me worth noticing outnumber the number of stupid, wrong, or bothersome things around me. The key is to take notice of all things, not just bad things. And for me, a blue sky, sunshine, warm day, or bit of nature outweighs a whole lot of negatives - as does a funny little kid tripping along with a goofy face or puppy dog prancing around make me forget about the rude guy who just cut in line. A whole day of positive observations or encounters can surely help the lesser number of negative ones that inevitably occur - if one makes a point to notice such good things.
By perspective, I mean assessing the real seriousness or inconvenience encountered with each negative incident or observation. There are two ways my perspective has changed immensely with age, and thus helped my response to negative things. First, I've aquired an interest in watching old WWII movies, including some live black and white footage from combat scenes of people being blown to pieces and hurt in terrible ways. There's a couple of related, incredibly powerful and depressing holocaust movies too, detailing stories of the starvation, disease, murder, rape, depression, and death that millions faced. With a large number of true based movies these days, a person can easily get a taste of the past and present attrocities occurring in the world, whether it be tortured prisoners, starving refugees, mutilated murder or rape victims, injured soldiers, or natural disaster casulties. A few hours of watching that occasionally can do a thorough job of letting us see and feel the extreme pain and suffering that millions in this world have to endure. And while we may not call such movies pleasurable entertainment, I think watching them does a person good - especially us americans that have an unusually easy, safe, comfortable life. Such reality check definately helps put a better perspective on the small, daily challenges and annoyances that most of us face and complain about. A second effect on my perspective has resulted from years of travel to 3rd world countries. This has clearly changed my scale of what is even noticeably wrong or bothersome. Spend some time in a poor, backwards country, and you'll appreciate just how polite most people are in the U.S., how orderly the traffic is, how quiet the neighborhoods are, how good the infrastructure is, how great the business service attitude is, how huge the choices are with groceries and shopping, and how safe it is with ambulances, hospitals, and competant police. The difference between life in the U.S. versus many overseas countries, if experienced first hand, is great therapy for putting a proper perspective on one's attitude with problems. I'd recommend a bit of it for everyone.
I think balance and perspective can definately reduce the scope of daily problems we all face, by diluting the negative perceptions with more positive ones, and by recognzing that the vast majority of negative issues we encounter or worry about either don't happen or don't matter in the long run. It's a life long effort learning this, but one worth pursueing for your own peace of mind and quality of life.
Your self image concerns are another matter clover4you, and you (as well as others on this thread) may not like what I have to say next. But, my goal is only to reach out and help if possible. You're free to grab the life ring or not, but I hope you may at least consider my councel as well as the others'.
Whether you accept it or not, the overwhelming scientific evidence is that you were created by a supernatural being - something beyond time, space, and matter; powerful enough to create the cosmos and life out of nothing; knowledgeable enough to create our complex minds; and loving enough to instill love and conscience into us as human beings. Such a being is best described as a god, and I'd confidently say that the god described in the Christian bible best fits that bill. I would also confidently say that, after considering a significant amount of the bible's textual criticism, historical documentation, archaeological evidence, and fulfilled prophesies, that the Christian faith is the only one, true religion in the world. No others can come close to having such verifiable supporting evidence. And in its inspired scriptures, one can read, understand, and appreciate that God not only created us, but that he created us for a purpose. So how's this suppose to relate to your sense of self worth, confidence, or concern for other people's opinions of you? It comes down to you needing to have a proper relationship with your creator. If you're a Christian, you need to gain your knowledge, strength, and proper world view with more bible reading, praying, and help from small church study groups. If you're not a believer, I'd suggest you give it some thought, since it's the most important thing in this world and life. When you have a right relationship with God, being the Father, Son, and Holy Spirit, you'll have immense peace in your heart, confidence in who you are, and strength to disregard others' opinions about you. In other words, the standard of who you are and how you're judged will be by God, not man. There will always be people trying to judge or influence you by their own shallow, wrong, or misguided opinions. Some are good or right of course, but how do you distinguish right from wrong, or the type of person you want to be? I'd suggest that the world's wisest old man, King Soloman, said it well in Proverbs 3;5-6:
Trust the Lord with all your heart,
and lean not on your own understanding.
In all your ways submit to him,
and he will make your paths straight.
Being a Christian entails having a close relationship with the one who matters most - your creator and savior. When you've got that right, living in this messed up world becomes much more manageable, your sense of self worth becomes well established, your purpose in life becomes clear, and your interaction with others fall into proper place As the heart and mind grows, so will your own self identity and confidence - because there's no feeling like knowing God's with you and you've got the most important thing in this life figured out right.
Finally, learning to love yourself as others suggest is good advice, but it's easier to do when you understand that God made you for a specfic purpose and loves you as the unique individual that you are.
Whether you dismiss this all or not, I wish you strength and will say a prayer for you. I'm free to talk more if you respond, but will check in here just once a week.