It is quite necessary, in order satisfy that inner (subconscious) desire to cross dress. I can put it on hold for a short while, but the need never goes away.
What I can control is when, where and how much. Thus the urge is less compulsory, even if it is almost always there.
I'm surely not going to die from not being able to dress, but it would make the urge stronger.
I have this itch on one spot of my belly that has been there for many years. I've seen the doctor for it, and had it biopsied, etc. Nothing has been able to stop the itch. I can ignore it for a little while, but eventually I have to scratch it.