I am a plant shrouded in mystery, revered for both my beauty and my deadly nature. Unravel my identity through these clues:

1. My roots can inhibit the growth of nearby plants, a characteristic that reflects my self-sufficiency.
2. I am often associated with themes of love, obsession, and sometimes, tragic endings in literature and folklore.
3. Certain parts of me contain potent toxins that have been historically used in arrow poisons and for other nefarious purposes.
4. My flowers are uniquely structured with five petals, sepals, and nectar spurs, blooming in hues of blues, purples, pinks, and white.