Yes, stress can indeed affect you like that and it is quite common to have both anxiety and depression. I think you may need to go back to your gp and ask for some talking therapy such as Cognitive Behavioural Therapy which might give you the tools to be able to cope with these panic attacks. It would also be a good idea to try to analyse where these feelings are coming from and what you need to do to be able to put your life back on track. It is good that you have understanding friends but you know, you cannot go through life depending on the kindness of others to get you by. You need to decide you will not be a victim to this illness. You will get better, and you have made a good start by coming on here to discuss your fears.
Good luck and keep posting!