Dealing with Anxiety
Some people are born with anxiety issues. Others go through some harsh times and if they aren't careful they can develop anxiety issues.
Anxiety is caused by stress. Another thing is it can be a build up of everything. For instance if you are around negative people and negative situations as time goes on, the stress will build until you can't take it anymore. You can even develop a panic disorder.
With the right help and trying to get on a positive track you could go back to your old self. You must always keep in check the enviorment, how your feeling and the people you are around. People who are in a positive enviorment are less likely to develop an anxiety disorder than someone who is in a negative enviorment.