Found: romance time travel

Dowdy linguist falls afoul of hitler-isic evil employer when she discovers instructions for time travel/Guardian? in ancient text
On the run after seeing her husband murdered, she becomes strong and self-sufficient, uses the formula to travel back in time in search of earth's salvation and lands in the the bed of a relentlessly lustful highlander.

Son of the Morning by Linda Howard

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touchstone: Son of the Morning by Linda Howard