Holy basil is a weak adaptogenic medicine, it can used for long term use with no side effects but the main purpose is for respiratory problems . You should try ashwagandha 500 mg 1 or 2 at night time.
More than Tulsi , ashwagandha can solve two endocrine disorders - adrenal and pituitary, both most needed for sleep. I tried organic India ashwagandha , other brands seem to be ineffective or gives hard pain near my kidney area.
If you ayurvedically increase serotonin levels , melatonin and other tablets can be also kept at bay.