Complex sentence: However, seeing her dressed provocatively to go on a date with another man, Ted camps out at her door until she returns, professes his love for Peggy and sleeps with her, making plans to leave his family for her.
Split into simpler sentences: However, seeing her dressed provocatively to go on a date with another man, Ted camps out at her door until she returns. He professes his love for her, they sleep together, and he makes plans to leave his family for her.