I want a manga where the one cheating is the girl and is the main character. She doesn't have to be dating one and then, later, cheat with another. She can be confused between two guys and then ends up with both of them. She doesn't need to end up with both or one of them, I just want this situation to happen.

Preferences:
Shoujo
Girl in her teens
Not being a complete bitch (but it's okay if she is too)

No:
Hentai
Harem
BL/Shoujo Ai

tl;dr:

• Cheating girl as main character
• To have feelings for the people she is having relations with (can be 2 or more)

Atashi no Mannaka (oneshot)
Yuuwaku Healing (only 1 chapter scanlated though)

Almost all are between two brothers, don't know how that happened.

Anata ni Tsunagaretai, Story 3) "The Devil's Mask"
Netsu Shisen (KANOU Noriko), stories 2 and 3
Teacher's Pet
Himitsu - H na Naishobanashi, story 1
Uzakoi, story 3, "Double☆Booking"
Warui Ko no Mikata, story 2, "Kono Otoko de Ii no ka?"

this one's josei -
Aisuru Hito