#2 You have a physical or chronic condition
Whether you have just found out about it or you have had it for a long period of time, it is best to think about going to therapy. Most people fall into the trap of thinking that the mind and the body are separate and that mental conditions and physical ones have no correlation at all.
The truth is that the two are always intertwined, and having something happen to your body actually impacts your mental state pretty heavily.
If whatever condition you have comes with life adjustments and especially if it comes as a shock to you, then learning how to cope with everything and deal with the uncertainties is something you may need help with.