Get over it, and don't waste any more time on this. Just be glad they were able to reroute without much delay. And MUC is a rather nice airport for a transfer.
Your logic is also a bit flawed, you got to fly one way without a stop I assume. These things happen in situations like this. It's the cost of flying....
If you already have contacted LH be a bit more patient, it takes them a while to reply. But don't expect much beyond an apology.