I respected idols who were not worthy of admiration, and because of that, I have seen, been a part of, and witnessed a lot of things in my life.

I respected idols who WERE not worthy of BEING ADMIRED, and because of that I have seen, been a part of, and WITNESSED a lot of things in my life.

If you start an independent clause in the past tense, you must maintain that tense throughout the clause. If say “are not worthy of admirning,” it implies that the idols are not worthy of admiring other things. Your intended meaning is that the idols were not worthy of being admired by you. There is also a tense error in the final independent clause: “witness” should be “witnessed.”

The answer above mine is also acceptable.

I respected idols who are not worthy of admiring; and because of that I have seen, been a part of, and witnessed a lot of things in my life.

or:

I respected idols who are not worthy of admiring. Because of that, I have seen, been a part of, and witnessed a lot of things in my life.