This is a song about trying to preserve something by refusing to name it. The speaker begs the other person to hold onto their words and heart while simultaneously refusing to say what those words actually are. The tragedy is that the silence they're demanding is probably what's killing the relationship in the first place.
Don't make me cry / Don't make me say it out loud
The speaker is literally saying it out loud in the song while begging not to have to say it out loud. That contradiction is the whole problem. They think silence is protection when it might be suffocation.
Better to burn out than to fade away / We knew the crash was coming anyway
They're quoting the Neil Young line like it's a shared philosophy, but then immediately admitting they saw the end coming. Fatalism dressed up as rock and roll rebellion. If you knew the crash was inevitable, why are you now begging someone to keep it alive?
You said too much and / Now it's too loud, too loud
The other person broke the unspoken rule by naming feelings. Now the speaker doesn't know what to say because the whole relationship was built on not saying things. Honesty is treated like a violation.
Keep, keep, keep it alive / Keep, keep, keep it alive
Four times in a row, like a mantra or a malfunction. The desperation is in the repetition. They don't have new words because they've refused to find any. All that's left is the same plea on loop.
Take, take, take my heart and, baby / Keep, keep, keep it alive
First chorus asks them to preserve the words. Second chorus escalates to the heart itself. The stakes are rising but the speaker still won't say what they actually need. They're handing over responsibility for their own emotional survival.
The song ends with 'keep it alive' stripped down to three words, no elaboration. The speaker has run out of ways to avoid saying what they mean. What started as a plea not to make them cry becomes proof that the crying was always going to happen. You can't preserve a feeling you refuse to name.