I do not own Game of Thrones
Rhaegar had travelled much faster than the news of Lyanna's speech in that village. That was why he did not find it out about what she had done until he stopped at his destination in Dorne. He almost lost control of his emotions. Why did she need to do that? Now he had to start contemplating from the scratch if this was the correct path.
What is a name? How much value does a family name have? This was a topic that he had thought about long and hard. If there was anything that he wanted to put out there and discuss with the maesters, it was this. Unfortunately those close minded fools who averted their eyes from magic or anything they did not like, as well as willingly threw away their family name were unlikely to give him a satisfying answer.
There was a time when even he had thought to abandon everything and run away from the Red keep like this girl was doing now. That was when he had started contemplating these things as a measure for the value of the Targaryen family name. What was it that separated them from the Blackfyres? Did magic only depend on bloodlines or were family names important as well?
There were 40 dragon lord families in the Valyrian freehold. It allowed them to inter-marry hence not lowering their bloodlines while minimizing incest. They already had documented cases of physical and mental defects born from it among regular bloodlines. Strangely in dragon lord families, it only gave rise to mental defects but not physical ones. Most likely reason was magic.
And yet Maelys the monstrous was born with two heads as the last of the Blackfyre lineage. His own father Aerys may have gone mad but never was a Targaryen born with anything less than the most beautiful features. Even Velaryons who had such diluted dragon blood were always defect free. And beauty equals nobility in this world. He idly wondered if the Night King was more noble than them but quickly discarded it. That way lay madness.
His conclusion was that Blackfyres lost the protection of family magic, the moment they abandoned the Targaryen name. The immunity to heat or hatching dragons were all beyond them now. They lost despite being better and then lost repeatedly even with a more skilled and disciplined 'golden company' as both magic and fate had abandoned them. This was the power of family name when added to the bloodline.
His greatest motivation for choosing the She-wolf to get his warrior princess Visenya was that only Stark name and blood could complete 'The pact of ice and fire'. The dragon must have three heads, and yet he was stuck at two. Was she even worth it anymore? Will her child truly be the champion he wanted for the long night? Or will it be a repeat of the losing streak with humanity's very existence on the line.
He considered alternatives like Kastarks but they weren't good enough to replace her. So he sent Arthur to Essos to look into the 'Company of Rose' to find female descendants of the Starks. She-wolf was still chaste so he could yet return her and earn goodwill of the North. But what if he was making wrong assumptions about the value of names? Should he keep her here anyway? But she would no doubt be opposed to him when she finds out.
In the end he decided to keep her but not do anything to her. She was young and not ready, and he was not a rapist. Not unless he was certain that it was necessary to be the hero who saves the world. With this he could return to lead the war and take the throne. That should serve as a good enough reason for why they aren't marrying. And so Rhaegar returned much faster than he should have.
