Wellbutrin + Lamictal Combo

Hi, I'm currently considering starting wellbutrin because of my recent lower mood and motivation. My therapist and psychiatrist think it could be signs of MDD and my body just constantly being in survival mode, but what's the difference between MDD and BPD depressive episodes that involve emptiness? Sometimes I just have more energy and motivation to actually work on myself and use the DBT skills I've learned, but other times I'll have periods of time where I have low energy and feel empty. Am I just avoiding feeling my feelings and then when I'm alone without any distractions my body instantly goes into that low energy mode?

As for lamictal, I've taken it for almost a year and a half now, and I went up to 225mg at one point, but I still didn't really notice anything. It was really hard to tell if the medication actually helped me when I started or I just had to learn to accept and cope with a really difficult situation at the time. I still don't know if lamictal does anything for me, but I still take 200mg of it everyday. The main side effects I'm worried about with wellbutrin are the insomnia and weight loss, since I'm already really underweight. I'm also trying to fix my extremely fucked up sleep schedule, so idk if the insomnia will impede my goal of trying to sleep earlier.

Basically, has anyone tried taking wellbutrin with lamictal, and what was your experience like?

Sorry if my post was a little incoherent, but please let me know if you have any advice or answers for my questions, thank you!