Oh Autumnlady, I'm really sorry that the silent migraine has floored you like this. Given that you know that they won't harm you, is it general anxiety that you're experiencing? Have you chatted this through with your docs? It's certainly hugely common at this stage in our lives.
I don't get the visual aura frequently, in fact only rarely, but when I do I just sit down and wait it out. I had one a few months ago when I was out driving and I just pulled over to the side of the road and switched off my engine. I was in central London and a traffic warden approached me and I was forced to explain what was happening and that it would be gone very quickly. Lovely chap, he waited there with me until it diminished which was about 30 mins later.
Whilst very little is still known about the migraine mechanism, it's now been proven that it is a genetic condition. It was very common in my father's family and sadly I've passed it onto my kids, though saying that, it's also prevalent in my husband's family so the kids had a double boost of the dodgy genes to inherit.
It may be that these will leave you completely, in fact you may never get another again. My mother suffered with them infrequently for a couple of years at meno and then they disappeared completely.
I wish you well xx