In the original series, Barnabas hid her body in the coffin and Ben Stokes later buried her in the woods. She had already told Joshua she was going to travel and had signed the documents giving up her claim on the estate in return for money.
Presumably, Angelique can resurrect herself with relative ease. She's alive again in 1840, so she resurrected herself some time after 1795 and before then. Additionally, she returns as Cassandra with relative ease and materializes in 1897. Her death was only final in 1840 because Gerard Stiles (Judah Zachary) removed her powers and made her mortal again.
Which explains, partly, why the writers went with 1841PT, to give Lara Parker a new character, Catharine Harriage, as well as Frid's Bramwell.
It must have been tedious for those two, watching all the others get to play fun new characters all the time. Cassandra, unfortunately, had the same voice styling, as did Catharine.
Why Lara didn't come up with something different is a mystery.