Complex sentence: At dawn, an infuriated Motiejus physically chastises Tadas for his lack of gratitude--that people have to suffer for him when saving him from trouble, while he does nothing in return for them.
Split into simpler sentences: At dawn, an infuriated Motiejus physically chastises Tadas for his lack of gratitude. He is upset about the fact that people have to suffer for him when saving him from trouble, but he does nothing in return for them.