TTC and being a bridesmaid...

My husband and I got married about a year and a half ago and are both in our early 30s. Since our wedding, we have planned to start TTC right around now, and we just started a few weeks ago. We liked the timing as far as having some time just to be married first, as well as planning around a vacation we had coming up (which is now over) and THREE weddings I was in the year after our wedding. 

Unfortunately, one of those weddings (which should have been this past summer) was called off last year, but I have just been informed that my friend and her fiancé are now back on with a wedding date in November - my friend assumes I will still be in the wedding, and truthfully it is important to me to be there for her. She's been through a lot (it was her fiancé who called off the wedding and her heart was completely broken - it's been a rough year for her obviously).

The problem for me is that now I feel I should plan TTC around the wedding, which would mean a potential hiatus from January-March. I've been told by my doctor that I may run into some difficulties and so I am not thrilled about waiting for three whole months.

I know some will say I shouldn't, but I when I was engaged one of my very best friends promised to be in my wedding and (unasked) told me it was great timing for her bc she and her husband wouldn't be TTC for their 2nd until after the wedding date we chose. A few months later I found out through someone else that she was indeed TTC and of course she wound up getting pregnant with a due date a week after my wedding. My feelings were very hurt, that she didn't tell me herself and that she didn't care enough to hold off for one month. We worked it out and I now realize that wasn't the case, but my point is that I know how important my friend/bride-to-he's wedding is to her, how much she went through to get to this point, and I know too well the feeling of getting married later than your friends - where everyone is on to "more important" things and your wedding falls by the wayside.

I want my friend to know how important she is to me and I don't want to let her down on such an important day. I'm DEFINITELY taking a break in the month that would put my due date in the same month as her wedding, but don't know what to do about the month before and after. I also know I need to talk to her about this (the biggest reason I was so hurt by my own bridesmaid was because she let me find out from someone else).  I want to be upfront with my friend and I want her to feel as important to me as she really is. 

I just also want to have a baby and was not planning on waiting any longer. It's not her fault her wedding was postponed, but when I agreed to this it was for a wedding that should have been six months ago. It's not always a me-first world and I don't want to be selfish, so any tips on how to approach this would be really appreciated. I think I need to find some kind of a middle ground between being a good friend and planning my own future.