"How to explain our disease to agents?"

Let's rephrase that.

How to explain our disease to family/friends/counter agents/FAs/CSRs on the phone, etc...?

They don't get it, most won't.

I did have a FA once thank MRers during the sweet deal AA had a couple years ago, (BOS-LAX/SFO 3x). She knew what was going on. On the flip side I was checking in for a flight from BOS-LAX-ORD-FRA and the agent looked at me like I had 3 heads. When he asked I shrugged my shoulders and told him I need the miles.

Like was already suggested upstream, just book it on via Kayak or another online service.