The answer is a relevant word.
This is a fun little puzzle! As clued by the bottom-most node of the diagram, which features an 'I' in brackets, each node of the pictured graph represents:
A letter of the alphabet.
Meanwhile, the numbers suggest that:
We should be able to spell out a thematic 8-letter word using the marked letters in the corresponding positions (note that the 6th and 7th letters have been left ambiguous by the OP, indicated here by question marks).
So how do we annotate the diagram? I would propose that we need to:
Identify a phrase that can be spelled out by passing from one node to the next.
But this could involve a whole heap of guesswork, right? WRONG
WHAT A TANGLED WEB WE WEAVE - it's the title to the puzzle, the only information we've otherwise been provided with! (Try and follow spelling out this phrase from node to node with your finger and you'll see it checks out...)
This means that our final answer...
...if we take the 6th letter the same as the 2nd, and the 7th the same as the 1st, is ENTWINED - a synonym of 'tangled'!
(Note that the otherwise symmetrical 'B' and 'D' nodes can be differentiated by the fact that using the 'D' in position 8 enables a real word to be spelled out, while the 'B' does not...)