They say your first Doctor makes an impression. Mine certainly did. He ran into my life in a trademark blue suit, skidded several feet, and screamed, “OH, I AM BRILLIANT!” … and I loved him for it. My Doctor does not wear a white lab coat (well, maybe once…) or use a stethoscope (well, okay, he does, but usually to listen through walls) or prescribe medicine. My Doctor saves worlds on a daily basis. He does it with sarcasm, cheek, and a British accent. My Doctor is Doctor Who of the classic, cheesy sci-fi series by the BBC.

Doctor Who is a weird show with an occasional liberal slant. I’ll grant you that. But if you’re British, you have been raised on it. It is to England what tea is to the Queen: an essential part of life. I wish I had been raised on it, but I discovered it as an adult many years later, ten different Doctors into the franchise. David was my first Doctor, and to me will continue to be the Doctor even after the “new kid” comes in.

The indicators of my emotional response to his departure are evident. Watching The Waters of Mars, several things happened. First, I got a lump in my throat when he walked out of the TARDIS with his trademark grin. You know the one: it says, “I am an all powerful and sincerely awesome Time Lord. I am also the smartest man in the room and dashingly handsome to boot.”

Okay, so I’m not sure how much of that grin is the Doctor’s and how much of it is David’s, but let’s not nitpick.

Anyway… I felt a lump in my throat, and it started to loosen halfway through the episode when he was lamenting on being the last of his kind. In the last ten or so minutes I felt a pain in my stomach and then in watching the preview for his final two episodes, my eyes got misty. In another five or so weeks, the Doctor will either Die or Regenerate and the fans will say farewell to David Tennant. If my family thought me losing Donna was bad, they are going to dread my reaction to this year’s Christmas specials. I came stumbling out of their guest room over the holiday and looked like the TARDIS had crash-landed on me.

“Uh-oh,” Mom said. “Who died on Doctor Who?”

Twenty minutes and one rant later, she was sorry she had asked.

Christmas is supposed to be a happy time! It is not supposed to start up my waterworks and leave me cursing Russell T. Davis’ very existence. I well remember that atrocious conclusion with Rose and the alternate universe. I remember Donna losing her mind and becoming “just a temp” one more time. I remember the Doctor having to leave her! I also remember temper tantrums and rants with friends and general angst. It made for a memorable holiday season.

However, Davis did manage to deliver this time. It’s not that creepy water-possessed characters that I will remember so much as the Doctor’s ongoing emotional journey. Long after the sinister fissure-like cracked faces vanish from my mind, the repercussions from his choice and that horrific moment in which the audience realizes how truly terrifying the Doctor could be will linger in our minds. Admit it. The wide-eyed Doctor, with an almost evil gleam, shouts that he is the Lord of Time and will force its obedience, and just for an instant we felt a bit sick inside. The Doctor does not lose it. The Doctor has more common sense than that. The Doctor is not supposed to go against the laws of time: some things are fixed events, and you do not tamper with them.

Throughout the series, there have been hints leading to this conclusion. Martha eventually ceased traveling with the Doctor because she had seen too much of what he was capable of. Donna said that the Doctor sometimes needs someone to stop him. And now you have the fierce Lindsay Duncan (who frankly scares me on her good days) staring him down in a snowy street and telling him he has no business controlling fate and meddling with time, and no one should ever have that much power — the power to change the world forever.

I have seen the dark side of the Doctor. I remember him locking a girl into a mirror and forcing an alien to spend eternity as a scarecrow. I recall the destruction of the spider-like creatures on his first meeting with Donna. The Doctor might have a conniption fit whenever he sees a gun, but he has time and again eradicated entire races in his pursuit of a higher purpose. The Doctor has always had a bit of a God complex — it is his choice whether races survive or are wiped out. It is an incredible burden to know everything and have a decision as to whether or not to intervene. It is getting to him. My Doctor is going just a little bit insane. Maybe it is knowing that the end is near that encourages his recklessness, or maybe it is just that at long last the sadness is hammering him, causing him to almost dare fate to take him.

It is a journey that has become more and more apparent with the passing of time and the that I believe we will see more of in the final two episodes before another writer takes the literary helm and steers us into a new destiny for the Doctor. I will give the new fellow a chance but somehow think it is going to be hard for him to follow in such big shoes. Like him or hate him, whether he is “your” Doctor or not — and with all due respect to Christopher Eccleston fans — I think we’re all going to miss David when he goes. Especially depending on the manner in which he goes. If he loses it, my heart will break. I have already cried over him many times. Remember when he was mortal for a time? Rip my heart out and stomp on it, why don’t you?

In many respects, I think the new Doctor must be completely different. But if that comes to pass, it will feel as if the true Doctor has actually died — and I don’t know how the fans could bear it. Which is more painful, having another actor dashing and skidding about in David’s tennis shoes or having no remnant of him at all?