I don't think the problem is with the logic...the problem is with adhering to structure. In other words, you have a pattern of meter and rhyme to adhere to...and you usually end up finding that the only way to finish the line with a rhyme sort of compromises the exact meaning. For example, maybe you wanted to indicate "conflicted", but had to settle for a rhyme like "sad", glad" or "mad".

It all gets back to the age-old truth: writing well is usually difficult, and simple lyrics that say it all perfectly...are hard to find.