The opposite could be true, or real, genuine.
True is the opposite of false, so the opposite of guilty would be innocent.
The opposite of true (factual) is false. It might also be unreal or fictional. The opposite of true (direction) could be skewed or angled. The opposite of true (loyal, steadfast) could be disloyal, unfaithful, or fickle.
false
false
No true is the opposite to false and Faithful is opposite to unfaithful or disloyal
false
Truman
False.
True
The opposite of relevant is irrelevant.
False and yes
The opposite of remaining true would be being false or untrue.