Know that when you walk in to that meeting, you are feeling just like everyone else who is there. That first time is very scary. Our life is not where we would have liked it to be, we are embarassed, we feel lonely, so very scared.
Know that you aren't alone anymore. These other people have lived through what you have, sometimes worse, sometimes not so bad. We now have others to share our experiences with. After the first meeting, we hopefully return. Or try another meeting. Give time time. You will soon know that you have strength in numbers.
I hope this can help. Can you get there today or tomorrow? Try to get a phone number or two so when you need to vent, someone can listen.
I wish you well,