I have to tell you that after 9 years of TTC and 6 DE cycles, two miscarriages and no baby, it was the 7th cycle, the one I was SO NOT into. The one that I barely remembered to take my meds, the one that I rolled my eyes every time something good happened (like the donor having 43 mature eggs). No special prayers, no good luck charms, no imagining what it would be like if it did work. I was just going through the motions because I knew it wasn't going to work. Well, it did. Maybe it isn't true statistically, but I think that if you are at it long enough, eventually the tide has to turn.
Only you can decide if you have it in you to do another cycle, and what you have been through is more than anyone should have to bear. Infertility is not for the faint-hearted. We-all of us--are warriors fighting battles and wars every day. The decision you make will be the right one. Even if you end up changing your mind!
Also, I think in the end it has little to do with how you are feeling. You don't have to feel positive or good for it to work. There were cycles that I was bouncing with positivity, but it was the cycle that I had no faith at all that ended up being successful.
I will also say this: the fear and worrying never ends. Once you are pregnant, then it is getting through the pregnancy. Now, it is making sure DD is breathing while sleeping, or eating the right things etc etc.
Good luck to you!