Ugh. Agoraphobia is no fun at all. I was housebound for 18 months at my worst, and getting out of the house can still be a struggle on bad days. I dropped out of school (and uni, and any number of independant courses) due to this and it really set me back in my education not to mention money!
Eventually I was hiding under the bed and crying because I could hear kids coming home from school on the street 3 floors below.... I knew then that just staying inside was not cutting it anymore, the 'safe' places were shrinking and shrinking.
That was when I really had to face up that just avoiding the places that made me anxious was not actually helping, because the anxiety was inside me, and if I made my whole world just one room it would still be there, in the corners and at the edges of whatever limitation I set for myself.
CBT and NLP (neurolinguistic programming) were what worked best for me in reducing the anxiety I felt, as well as general anxiety reducing techniques like balanced breathing, mindfulness, meditation etc.
It was slow going and there were a lot of years where it was hard to hold down a job or friendships because leaving the house was such a massive ordeal, but I am now able to hold down a job, have something of a social life, do my own shopping and even occassionally go to a show or public event (still a challenge!).
I also found that even in 'maintenance mode' I have to make sure I get out of the house once every couple of days at least, I have to push those boundaries a little beyond comfort on a regular basis, or my world starts to shrink again.