So, just catching up here, but as someone also recently (finally) diagnosed as bipolar and trying out new medications...
It sounds like the Lamictil might not be working for you in a way that is giving you positive benefits. It might be time to call your psychiatrist, honestly bring up your issues, and try something else. Because issues with sleep were a huge problem for me that made everything else worse, we ended up going with a low-dose antidepressant, setraline, combined with an anti-anxiety medication that has a mood-stabilizing effect, clonezapam. End result, I'm not depressed all the time and I am mostly able to sleep except when I'm really seriously in a hypomanic way, and then I still have trouble falling asleep, but can get there eventually.
The combo has been really working for me in terms of sleeping and not being a depressed sack of depressed shitty shit thinking about suicide all the time, but it doesn't entirely modulate my moods. Which I honestly think is a good thing. I like being able to FEEL THINGS. The bringing up issues and concerns with medications thing has been hard for me, but I found a psychiatrist who treats me like a fucking adult and takes my issues seriously. It's my life after all.
Anyway, I feel for you. I'm hoping you are able to find something that works for you.
To whoever asked about lithium, my psychiatrist said they tend to go with Lamictil over lithium for bipolar II when I asked about it (my first fiance had bipolar I and was on lithium so I was curious and asked). It tends to not destroy the kidneys as hard.