I was the same way for a long time! I had thousands of hours between the Xbox and PC. Four in total that I loved to play. But I started to take long breaks after a while and every time I tried to get back into it with a new character I'd lose interest quickly.

Until!! I set myself challenges. For instance:

I rolled a blind Breton pacifist who would never kill anything herself. I worked on her alteration, illusion, conjuration and restoration trees and I had the HUD display turned down to zero. It helped me stay in character with her because it crippled me in a way. I couldn't see where I was going because there were no quest markers and I wouldn't allow myself to view the map, so I had to rely on my knowledge of Skyrim to locate dungeons etc. I couldn't tell if I would get into trouble for stealing something, I would fumble to pick up items and accidentally steal a bottle of wine and have to run from the guards. It was really fun and challenging!

Getting into the character and roleplaying as them helps to keep me coming back. I had a wood elf, who I decided could only heal with food she'd hunted herself or use potions she'd crafted herself. She excelled in alchemy, light armour, smithing and archery. She was a young, feisty character who had little to no patience for most other races. I loved the idea that although she was rather rude to everyone else, she doted upon Faendel and I had her take him as a follower and pretended she viewed him as a father figure and she would always behave herself in his presence.

I challenged myself to create the prettiest orc I could and played her as a merchant, who looted dungeons and travelled Skyrim selling her wares and helping out the Khajiit traders. She wasn't one for battle either.

I suppose I'm saying that if you're finding Skyrim repetitive, perhaps it's because you're not trying anything new. And there's lots of different ways to play Skyrim. Maybe come up with a backstory for your character, find reasons he or she can't do this or only uses that. Set little challenges for yourself to make things interesting again. Good luck!