I was trying to understand this sentence
kimi no senaka o boku wa tayori ni shiteitanda
kimi no senaka = your back boku = I
And I can't figure out what tayori ni shiteitanda means
jisho.org says tayori is a noun, dependence
Also, this webpage says noun + ni suru (in the case shiteitanda is related to suru) can be used to "decide on" a noun, ie "I'll go with.." . So may be this could be something of the form "noun + ni shiteitanda" assuming shiteitanda is related to suru, and since there is a "noun + ni suru" form but that's as far as I can guess. How does it translate noun + ni + shiteitanda?