Recurrent vaginal infection

I've been having recurrent vaginal infection and it's making me paranoid and stressed out. I try to avoid washing too often because i know that might kill the good bacteria needed. But sometimes, I can't help it. The last time i had a vaginal pessary but it led to a missed miscarriage. So I'm scared to take another one. Are there alternative treatment options or medications that can help put this at bay for longer periods?? Any advice for me to manage it better? I don't know what's causing this and I'm afraid this recurrent infection might affect the baby. Currently 18 weeks pregnant.