A nurse shouldn't be passing on their personal opinion based on things they have seen, they have no idea of the patients' personal / medical history, they have no idea how compliant the person has or hasn't been post op. They Non-compliance could well have caused some of the issues they have supposedly seen. Talk to your doctor/surgeon about the concerns that she has caused you to have.
You have obviously considered WLS because you are overweight and its usually not a first choice for weight loss, so I would say you have tried and failed at various weight loss methods. What will you do to lose weight if not WLS?
I am sorry to hear about your friend, but was it confirmed that five years after WLS, that WLS causes the bowel obstruction.
At the end of the day, you have to do what is right for you and what you feel safe with, but you should research further with other medical staff - your doctor, bariatric surgeons etc.