Why now?

I've been noticing a change in me lately and I'm wondering why it's happening now.

To give you some background, I have always been the sort of person who puts the needs of others before myself. If someone cut me off in traffic, I would think "Maybe they're having a really bad day, and just needed to take it out on someone," and I would continue on my way without reacting to it. It never really bothered me to think that people took "it" (whatever it might be) out on me.

Until now.

The simplest thing happened yesterday. As is common in Honolulu, I was waiting in a line of cars to get into a small parking lot in front of where I was going for dinner. The line was moving slowly as people were stopping to punch out a ticket before proceeding, but it was moving. As the car in front of me went to punch out a ticket, the woman in the booth stepped out and placed orange cones behind the car, blocking my entrance. I lost it.

Why did I loose it? Was it HER fault that the parking lot filled up right at that moment? No. Was I angry that I would have to drive around another 5 minutes in circles looking for a space? No. Was I angry that I would have to walk a further distance from my car to the restaurant? No.
I was mad because she didn't even look at me. She just walked out of her booth and put the cones up like there was no other car in the world. As if she were moving furniture around. She blatenly went out of her way to ignore my presence. THAT, my friends, was the straw the broke the camels back.

I'm not going to go into detail of my behavior. In most aspects, it wasn't bad. I didn't get out of the car and assault her, but I did assault her with my words. Luckily, the window was rolled up still. But why would that bother me so much? Why this? Why now?

Do people really have a number of times people can be rude to them before they blow up? Each person has a different number of course, but why am I so concerned with people disrespectful me now? I never was before....What about me has changed?

I'm not sure if this is a good or a bad thing. My boyfriend seems to think it's a good thing, but to be honest, I feel angry and resentful all the time now. Maybe I'm feeling angry and resentful and THAT's what is causing me to loose my patience. Maybe I'm sick. Maybe I'm tired. Maybe both. But why now?

This is worrying me.