Nepal was never colonized, period.

However, Nepal has been living under the hegemony of British India and, later, Independent India, since Jung Bahadur's time. 

While we are a sovereign nation.  Our domestic and foreign policies have always been heavily influenced, and even dictated in some cases, by the south block. 

Our historical record show that Nepal, in some shape or form, had to pay homage to China and Tibet from time to time.  But that has never been consistent and is negligible.  Same cannot be said with our souther neighbour.