Complex sentence: He had no descendants with Hortance Lacoste who was 50 years old at the time he married her, but before marring her, he had a long relationship with Mrs Elise Romain.
Split into simpler sentences: He had no descendants with Hortance Lacoste who was 50 years old at the time he married her. But before marring her, he had a long relationship with Mrs Elise Romain.