Odin later drew the spirits of all Asgardians, including Sif, into the Destroyer to fight the Celestials and prevent their judgment of Earth. The Celestials destroyed the armor, but the Asgardians’ spirits were restored to their bodies through Thor’s efforts. Following their reunion, Thor again implored Sif to accompany him to Earth. The two were betrothed, and she agreed to join him later. Sif spurned the advances of Asgardian war god Tyr and eventually reunited with Thor when her latest rejected suitor and Loki forced the Asgardians to flee to Earth.
After Tyr’s defeat, Sif stayed on Earth with Thor. She briefly assumed vampiric qualities after being bitten by Dracula, who desired her as a mate, until her Asgardian physiology rejected the process. Sif was unsatisfied with mundane life on Earth, and constantly lonely as Thor spent his days as Blake. After accompanying Thor and Dr. Keith Kincaid to rescue Jane Foster, whose essence had dwelled within Kamo Tharnn ever since Sif’s reemergence, the shield maiden returned to Asgard while Thor stayed on Earth, ending their betrothal.
Sif, saddened by Thor's love of Earth, changed with the arrival of the alien Beta Ray Bill, whose strength and nobility had proven equal to the God of Thunder’s, leading Odin to grant the cosmic crusader his own mystic hammer, Stormbreaker. After defending Bill’s people from demons, Sif, with Thor’s blessing, left with her new love interest to protect his people as they searched for a new planet to call home.
Sif and Bill returned to aid the Asgardians and Earth's heroes in oppositionn to Surtur’s armies. Sif led Valhalla’s fallen champions against Surtur’s demons in New York City, and was injured in the battle until an elixir restored her. After Odin seemingly perished defeating Surtur, Sif devised a way for Thor and Bill’s hammers to return the stranded Asgardians home, and planned to leave her current beau and return to her first love. However, Thor was under the goddess Lorelei’s love spell and struck Sif. Conflicted, she resolved to leave Asgard permanently with Bill, but was dissuaded by Thor, who swore his love; Sif said her goodbyes to Bill.
Sif was later heartbroken when Odin, secretly possessed by Loki, ordered Thor banished from reality. She ritually cut her hair and embarked with Balder to find her lost love. Using Karnilla’s Norn Stones to find traces of Thor’s essence across the universe, Sif and Balder traced their quarry to his mortal replacement, Eric Masterson, on Earth. During their quest, Sif turned to Mephisto for his help. Masterson and Balder followed her to Mephisto’s realm and she fought them until realizing her own obsession. After sharing a kiss with Masterson in a heated moment, Sif learned from Mephisto that Loki had secretly usurped Odin’s throne. They returned to Asgard and restored Odin to his rightful place, and learned that Thor had been imprisoned within Eric Masterson’s mind. Sif was briefly torn between Thor and Masterson, but ultimately reunited with the God of Thunder following his return.
However, they were separated again when Thor succumbed to the warrior’s madness, becoming extremely violent. Sif and Beta Ray Bill tried to help him and fruitlessly sought the help of many others, but it wasn't until Thor was incapacitated by Thanos and brought before Odin that his madness was cured.
Thor was bitter toward his father for years of manipulation, and Odin angrily banished Thor from Asgard, replacing him with the resurrected Red Norvell. Sif resented Norvell’s usurping Thor’s place, but achieved a sense of camaraderie with him before disobeying Odin and joining the original Thor and his new allies, the High Evolutionary and the Godpack, on Earth.