More similar to yours than one could possibly imagine.

• A centre-left incumbent that seemed on track to lose, as of February.
• Thanks in part to Trump, the incumbent saw huge swings towards them in the polls during the campaign.
• So much so that their conservative opposition lost his own seat.
• The unfortunate harm done to a real left-wing party as a by-product (in your case it was because of FPTP and strategic voting. In ours it seems likely to be an unintuitive byproduct of how IRV works).
• Your left-wing party lost his seat. We’re still counting but it looks very possible that detail could be replicated here.