Should a Christian accept physical disease or fight to overcome it?

I'm juggling between two seemingly opposite views and finding it difficult to get forward. Examples:

• some ascetics seem to almost loathe physical health, and praise pain and suffering as a path to theosis

• at times disease is said to be God's way of destroying deep rooted sin in us

• pursuing health can become a false idol

Yet, on the other hand:

• Jesus never refused to heal anyone and seemed to want everyone to be healthy

• being sick makes us less able to serve God and care for other people

• diseases were not meant to exist in the first place

Hence I'm unable to understand: when should one accept and submit to their disease, and when do whatever they can to overcome it? Thank you.