It sounds like you're dealing with a complex and emotional situation, here's a summary of the story:

1. Confrontation: You’re confronting someone about a potential betrayal, accusing them of cheating on you with your sister.
2. Suspicion: You’re worried and confused because your sister and Josh are together. You're questioning their relationship and the nature of their interaction.
3. Gifts and Jealousy: You noticed that Josh gave your sister a gift, which makes you feel jealous and suspicious, especially because you believe Josh doesn't like your sister.
4. Uncertainty: You’re struggling to understand why Josh and your sister are together and what their relationship is, leading to doubts and mistrust.