Pitcher plants (Sarracenia sp.) will put out this kind of leaf when stressed. If you kept it inside in the winter months, it may have not got the dormancy it needs. There are other factors too, like how much sun is it getting, what is the growing medium, etc.

Here's what they need in the nutshell: sunny conditions, a peatmoss based medium (best to mix with some quartz sand), and lots of mineral free water in the growing season. In winter they need temps at least below 50F for a couple months, but can endure much more harsh conditions. It doesn't really matter which species you have, they all respond to same conditions equally, more or less.

To wit, if you haven't done so already, give it sun, lots of mineral free water (no chlorine!!!), and peaty soil. It may respond favorably. Good luck. PF

If and when your pitcher does come back. In the fall leave it in the bog for the winter. You can mulch it with a covering of pine needles or straw. best of luck