What does stress have to do with Crohn's disease?

Hello doctor,

I have Crohn's disease. Two years back, I was fine. I had gone through extreme stress early that year and after that, I had a flare-up. I lost 9 kg in a month. Then, the doctors detected ulcers in my ileum I was diagnosed with Crohn's. I was out of work for 14 months. Assuming that it is a genetic or immune system-related disease, I have a couple of questions.

1. Does it initiate due to stress?
2. Does Crohn's get worse due to stress because now I need to take Humira every alternate week?
3. Does the ulcers/flare-up happen due to stress?

I am currently on Humira (Adalimumab), Azathioprine, and Omeprazole.

Thank you doctor,

My medicine is working perfectly. I never had a flare up/stomach pain since five months. I am normal at present and I gained 37.4 lbs. But that is not my question. My question is different. I wanted to know what caused that flare up. In every article on the internet, I saw that Crohn's is caused by genetic, immune system problem or environmental issue but stress can cause a flare-up. In many cases, patients, when diagnosed with Crohn's disease, were extremely stressed. So, I wanted to know the reason.

I was fine just two years back. Two years back something happened and I had an emotional breakdown. I was not sleeping and crying most of the day. And then I started having loose motion and vomiting. I could not eat food and my health suddenly deteriorated and I lost more than 9 kg in a month. So, earlier I was thinking that it was caused by the stress. But after research, I understood that stress is not the main cause of the disease but stress can cause a flare-up or worsen the existing condition.

So, I am emailing you all my reports and want to know what caused that flare up. I was out of work for about 14 months for that flare up (six months at home). I had extreme joint pain and I could not walk for two weeks. I had a severe deficiency of vitamin D and B12 and my doctors here told that I could have permanent damage to my nervous system.

So, I wanted to know the reason for that extreme flare up. I could not visit a doctor to know the reason because it will be expensive. That is why I am asking you.

1. Does it initiate due to stress?
2. Does Crohn's get worse due to stress because now I need to take Humira every alternate week? If I stop Humira for a week, then I start having lose motion. So, does stress worsen the disease?
3. Does the ulcers/flare-up happen due to stress?
4. Why that flare up happened when I was extremely stressed? Is there no relation?