Does my string of heart need more water or light? Why so thin?? Please help me here. 😔

It is a stringy plant. You have to make cuttings and plant them in the same pot.
Here is one how to on YouTube
https://www.google.com/search?...

LorettaNJ said: It is a stringy plant. You have to make cuttings and plant them in the same pot.

Yep.

Seems like a fairly healthy plant with some watering issues.

Missing lots of leaves and some completely dead vines, from under-watering is my guess.

I'd cut them. They're still using the plant's energy but aren't giving any back.
Cut them and try to root what you can.
If you get anything, replant up top.

And cut the longer ones now to replant.

I found this video and she's got a very cool method, many plants I want to try it on!
https://www.youtube.com/watch?...

And water more.

It's been a cold dry winter.

Plants slow down but dry air takes a lot of moisture out of the soil and leaves.

Thanks guys. All the videos are very helpful! 😀