Hello - congrats, and well done on dealing with your BP:)
I USED to suffer with depression years ago. When I was P with DD who is now 2, I got anti natal depression (AND) from day one and turned into a different person, I was so worried about the birth and post natal depression (which i never got). As it turned out, I got to 42 weeks and was so desperate to get her out, it blocked out any other thoughts I may have. I was determined not to have a CS, as the recovery would have done my bloody head in - I wanted to be pain free asap, and saw a VB as the way to go for me. All was ok, induced with an epidural for the discomfort.
After her birth, I had my low days - as does any mother, but they were few and far between. With pregnancy 2, I got AND again, but was determined to go the totally natural route, with no drugs. I read a Hypnobirthing book, purely for the positive outlook on birth - I would really recommend this, whether you have cs or vb as it really is positive, and makes you think you can do it:0) There are some great breathing exercises in it - I felt great after reading it. I also downloaded some relaxation music - BTW, I am the MOST unhippy, unrelaxed person, and all my friends were laughing at my new mother earth attitude with my aromotherapy oils and music:)
I also had lots of refelxology in the 4 weeks up to the birth to stimulate the muscles needed in preparation - basically, I spoilt myself in the run up, and I felt soooo much better than the first time I did it.
Now, I'm not meaning to brag, and it was my 2nd so things were a bit used to doing it, but from 1st contraction to DS being out was 1.5hrs, the pain was totally managable, but the best bit was afterwrds - the high was great, i felt very overwhelmed:) I'm saying this as it's sad that women get terrified of something natural. I'm not anti CS, but I feel some girls are so scared when perhaps they shouldn't be. There are too many horror stories.
Do whatever you feel is best for you, but I would recommend the hypnobirthing books as they may relax you. As for PND, keep talking, don't get isolated, and remember there are always those to help IFFF you need it. YOu may very well find you don't, but it's good that you are prepared. As others have said, keep your GP, mental health team posted and have plan. Try not to get stressed about being P, it's life changing, but great:)
And now for something abit TMI - if you consider a VB, try perinneal massage!! This will truly make you embrace the magic of pregnancy:) Joking there, but it does help.
On that note, good luck and enjoy x