Hi. just querying your actual dx. Do you have BP for sure or BPD? Or both? DBT is for people with BPD, and that doesn't require meds for effective treatment. Sorry to be honest, but I kinda agree with what the nurse said, in a way. If you really have BP it is virtually impossible to treat med-free. The most successful way to treat it is with meds, therapy and a strong support network. And you need all 3 of those things for it to work. BP is a chemical imbalance that needs addressing. BP is possibly the hardest psychiatric condition to treat because of the complex relationship between depression and mania, and the difficulty of finding the right balance of right med, right dose.
If your main worry about meds is about side effects then you just need to keep experimenting until you find one that suits you. I return to my doc straight away if I'm unhappy with a side effect. There are newer meds available now with low rates of side effects. I've found 2 meds which cause me no side effects, so it can happen, believe me. It is true that BP can worsen with time and age, and the older you get the harder it is to treat. So you need to get to a place where you're more accepting of your condition and start getting the proper treatment for it before it's too late. Maybe you should look into BPD and decide whether you think there's a possibility that you may have it, because you may have been misdiagnosed with BP. Like I said earlier, if you do have BPD instead, then you don't need meds at all, just DBT and therapy.
Good luck, take care and keep us posted about your progress and any other developments.