First of all have you realized that by talking about your problems, you are helping us feel better (we are not alone) and given us the possibility to think a bit about our situation and how we manage it ? Does it feel "unimportant" for you ? I guess not.
Which means not only that what you have to say is interesting but by telling it you are helping somebody. The beauty of it is that you don't know who you are going to help and how much.
Now let's try to answer your question. First of all I'm coming from a background where everybody is REALLY judging everybody. My parents are tunisians and, in this country everybody seems to spend their time checking on what other is doing or saying. So you can imagine, as the only christian, living in France, working for the french government and living with a french catholic guy, how much my life was critisized but here was the starting point in healing for me : One day something very bad happened to me and when I needed help, all those people who were used to tell me what to do or say and judging me all the time, just disappeared. They were able to spend time judging me but their judgements were useless when it came to really help me.
When I realised this, I also realised that those people and judgements were, in fact, worthless and the only person who really cared was me. So I decided to no longer care about them either.
That's where I started to work on my anxiety symptoms.
There is something else I discovered that greatly helped me. I (and surely you) am not anxious for the cause I think. For example, in the case of the party. I go to the party, feel anxious and think "I knew it wouldn't work, I hate parties" but it's not the real reason. You see the brain is kind of loving giving automatic responses. You go to the party, you feel anxiety with no reason (most of the time you feel it before even seing anybody) and THEN your mind searches a valable reason for the symptom like "they are going to judge me" etc....
So it's not the party that makes you anxious. You are anxious on "automatic response" and then you search a logical reason for that and decide that "it's the party".
What to do then ? Well I'm here to heal myself so I would of course suggest you to take the social anxiety course like I am but in the meantime, knowing that it's an automatic response of your brain and not a real fact (no, people are not judging. No it's not because of the party) can help put the things on perspective.