The mother-in-law

From the moment Lucy met her husband's mother she knew she wasn't what Diana envisioned. Now five years later Diana has been found dead--a suicide note near her body claiming that she no longer wanted to live because of a battle with cancer. But the autopsy finds no cancer only traces of poison and evidence of suffocation. Who wanted Diana dead and why was her will changed at the eleventh hour to disinherit both of her adult children and their spouses?