You probably want to understand first what causes the anxiety and panic attacks, and once you understand you want to chose the best way for you. There is lots of literature around, or you can simply see professional help. Some quick points:
There are several causes of panic attacks and underlying high anxiety, such as certain medical condition, overreacting adrenal glands, certain medications, stress, or it might be hereditary (in family), due to genetics predisposition, neurotransmitter imbalance and so on. It can also be learned response. A person can have panic attacks with or without agoraphobia (when certain environment is perceived as dangerous, e.g. places or situations from which the person cannot escape easily).
You'd probably want to analyze what causes your anxiety/panic attacks, it may be difficult as it could be any combination of the above.
To deal with it, the simplest answer is medication, but there are also different ways:
You had the panic attacks three years ago, and then you started to experience them again three months ago when you were thinking about old anxious ways. This was your trigger, by thinking about it you simply brought it back. Another trigger(s) could be some negative self talks in a form "When I see a girl next time I'm gonna panic"
1. So be aware of your trigger(s) consciously, then try to avoid them, or deal with them in a rational way. Find out if there is any negative self talking and change it to positive. Try affirmations, perhaps something like: "I used to get panic attacks but now I am doing much better". "Its ok to think about my past panic attacks, now I have much better tools to deal with them". Do lots of them.
Here is couple examples of your negative self talk, your negative believes:
"If facing my fears didn't work then, how will it now?".
"I am not comfortable even all by myself".
"It makes me feel sick and depressed".
"It brought me back down"
"I had a panic attack, then another one. Then again, and again, and again,..."
You put yourself down with the above, you don't trust yourself, you flood your brain with negativity - while expecting positive results. It doesn't work that way.
Change those believes to positive ones, flood your brain with things that work through more positive and reasonable affirmations:
"It is ok that facing my fears didn't work before and I'll do my best so they work from now on".
"It is ok to have anxiety attacks, I can deal with it much better now".
"I wasn't comfortable with myself before, true, but now I am getting much more comfortable".
"I used to make me feel sick and depressed, but now I understand much better, and I am focusing more on positive thoughts and feelings".
"It brought me down, ok, no big deal. I am up again and ready to deal with it".
"It is ok if I have another panic attack, I accept that because I will be able to deal with it much better"
"I was already dealing with panic attack really well, and I will be able to deal with it even much better because now I know how"
"Panic attacks are ok, no big deal, they are actually quite interesting" (attempting to rationalize and minimize with logic)
2. Keep practice good feelings, relaxation, meditation. Good/positive feelings. First at home, then when you are among people. Practice slow and deep meditative breathing (home and among people). Panic attacks can actually be caused by high oxygen in your brain, as you are breathing very fast your oxygen level increases and your brain starts to "panic" (thus breathing into paper bag may help as you are re-breathing more CO2 and less oxygen)
3. Use systematic desensitization. If something specific causes you high anxiety try to overcome it by systematically exposing yourself to it (e.g. if girls cause you high anxiety, start slowly approaching one or two, then gradually increase the number. Maybe another of your trigger is to be alone (in the woods, in the shower,...). See how much time you can be alone while remaining comfortable.
4. Plan ahead what you are going to do when you start feeling that you are getting panic attack, have exact plan ready: Leave the situation, call friend, slower deep breathing (into paper bag), ...
5. Accept the panic attacks/high anxiety. If you try to fight them it will increase you anxiety as you will fear that you will be overwhelmed. Acceptance of anxiety may actually calm you down, thus avoid the attacks.
"It is perfectly OK to experience panic attacks".
"I'm ok with panic attacks, they can come and go, no big deal"
6. You can use some NLP (visualization) techniques. It would be quite long to write about it, it is much easier if you google it
So, you have lots of "tools" to deal with it: you have the understanding, you can make clear plan and can easily keep practicing the above...
Hope it helps