信頼 and 依存: trusting a friend and depending on something
Compare trust in a longtime friend with dependence on income or medication, reading 依存 as いぞん and preserving the scope of the income example's negation.
Trust in a longtime friend
信頼 (しんらい) means trust or confidence. “約束を守ることで少しずつ信頼を得た。” describes gradually earning trust by keeping promises.
“長年の友人なら安心して信頼できます。” says that a longtime friend can be trusted without worry. Preserve the なら condition rather than turning it into a rule that every friend is always equally trustworthy.
Income and medication as objects of dependence
依存 (いぞん) means dependence. “一つの収入源だけに依存しない仕組みを作った。” says that a structure was created that does not depend on only one source of income.
In “薬への依存について医師に相談した。”, the speaker consulted a doctor about drug dependence. Read the consultation topic and action without adding a degree of dependence, a diagnosis, or the consultation's outcome.
Compare a trusting attitude with a dependence relation
信頼 in these examples concerns trusting a friend, while 依存 concerns depending on an object. Dependence alone does not automatically establish a feeling of trust in that object.
The income sentence negates dependence on only one source. It does not say the structure depends on no income source at all, and the example does not supply financial advice.
Does a structure that 一つの収入源だけに依存しない depend on no income source at all?
Show the answer and why
No. It avoids dependence on only one source of income, without negating all dependence on income sources. 依存 is read いぞん in this example.