At your age the most likely culprit is your age, older eggs etc, unfair though it is.
There is possibly not much that you can do about that (v little research that shows any positive results), but there are various things you could try without massive expense. A book called "it starts with the egg" makes a load of recommendations as a result of which I take ubiquinol, vitamin C and alpha-lipoic acid as well as fertility multi vitamins, fish oil and extra folic acid.
I appreciate the thought of the hsg is not nice, but it really is the quickest non-invasive way to check your tubes. And if you were to want ivf, you would probably have to have a hysteroscopy beforehand, as there is no point in creating embryos if the environment in which you want to put them isn't good. Maybe speak to your doc about this; you could be sedated for it if that would help (although a nurse did mine in 10 minutes at UCH and it was totally fine- and I have nearly cried in a smear before!!).
I think some ivf clinics might recommend a donor egg (I know, it's a lot to get your head around), so that's worth bearing in mind if you wanted to go that route.
There's not much evidence to support use of acupuncture, but I do find it helpful for dealing with the emotional side of things.
Other things - High protein diet, making sure your weight is right, no smoking, very little alcohol, a bit of exercise when you can - may help, but I kind of think that if it is going to happen a little occasional glass of wine isn't going to prevent it.
Finally, DHEA is recommended by some doctors for older women undergoing IVF although there doesn't seem to be much "good" evidence supporting its use and very little to say what impact it might have on a natural cycle. But who knows? It is supposed to improve egg quality. Maybe it is worth a shot, but it's one of those things you have to buy on the internet which makes me too nervous to try.
Best of luck, as a fellow ttc-er wondering about next steps, I hope you get what you want.