I completely agree this TTC journey can be a horrible cycle. We can have the highest highs (when we get the BFP) and the lowest lows imaginable (the loss of the baby). We have to be superwoman to even make it through some days. We put on these brave faces to our friends/family IRL and that sometimes just makes it worse. The good news is that we have each other here. Here, we can rant, despair, cry and say everything that is too hard to say to those we are closest to.
I am in the same place you are right now - 8 IUI's, 1 IVF resulting in 1 miscarriage and one tubal pregnancy and 6 BFN's. I feel that this will never happen. But that is today (ok - and yesterday and the day before that). I know I will feel differently in time. And that is one of the worst things about TTC - we can keep saying "next month"...
I agree with the other ladies about finding something for you that can take you away from the stress for just a bit each day - yoga, 5 minutes listening to your favorite songs, something. The stress sucks.
I am sorry you are having such a difficult time (and where do all these pg ladies come from during this????!!?? It is an epidemic, I swear

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But know you can always come here and we will do whatever we can to help - send hugs, just listen (ok, read)...most of all, I think we all "get it". And sometimes, that is the best medicine. Not feeling so alone. I know having these ladies to unburden myself to has helped me immensely. Now if only they could actually get us all pregnant, they would be true heros.
**HUGS*** You will figure out the right path for yourself - whether you continue or not. And heck, sometimes those decisions are made for you. How many times do we hear those horrible stories of women giving up then getting pregnant???