You may purchase travel insurance even if you are an independent traveler making all your own travel arrangements. 

Related articles:

• Does travel insurance cover a loss due to the financial default of my travel agent or tour operator?
• May I add coverage to my travel insurance policy after I purchase it?
• May I purchase travel insurance up to my date of departure?
• May I purchase travel insurance up to my date of departure?
• I booked part of my vacation, but not the flight. I would like to purchase travel insurance within the pre-existing condition exclusion waiver period. Do I have to wait until the flight is booked?