Toronto94

To the first question, yes, it's standard to be anxious about a big life change. The question is just whether it's worth it, for you. I note that almost all of your later career goals involve a big move, also to the states. So, given that eventually a move is inevitable, what's going to be different later on? In order for you to get to what you want, you will have to make a big move eventually. So, why not make the move now if it's going to give you a big advantage later on?
If you really do not want to move, then that's understandable and you should not have to. However, if you are just having the normal anxiety, my advice is to think of the benefits to moving. You'll miss your old friends but you'll get to have a lot of new experiences too! I learned a lot more about myself and what I actually liked/didn't like after moving for the first time. I also found that time away helped me "reset" myself a little bit. It was like a mini purge of my social network: I felt that there were some connections/relationships that weren't really that important to me but still took up a lot of my time or energy, and adding distance made it more clear who my true friends were and who weren't really my good friends. There's a lot of crappy downsides to moving too of course, I was around for the first few years of my cousin's kids but now many of them are much older and I am missing out on being around for my cousins' newer children. But I still felt like I gained and grew more as a person being away and being challenged than I did if I were to just stay in a comfortable place forever. 
I think setting up a self-care plan is a great idea and ensures that you stay connected to what's important. In addition, another thing that helped me was to determine a long term "exit" plan. I had decided that I would give the "academic nomad" thing a try for 10 years maximum---after that, no matter what, I wanted to be close to home. For me, the worst thing about moving for school was that I had no idea where academia might lead me. I know many people who move for postdoc after postdoc and not being able to settle anywhere for a long time. I think giving myself an "end date" to moving around and choosing moves that I know will lead me to my ultimate goals helped me cope with the uncertainty of academia. 

Hey! So, firstly, congratulations on your UC Davis acceptance. I will say, though, that I think it's totally normal to second guess your initial excitement about uprooting yourself from home. Home is comfortable for you. Going anywhere else for a fixed amount of time (months, years, etc.) is anxiety-inducing regardless of how ready you thought you were. So I think it'd be more strange if you weren't having these thoughts (even if you didn't voice them out to anyone). Now, admittedly, I'm not in your field. So take my advice with a huge grain of salt, but I think you have to figure out what your end goal is with a doctorate degree. Many want to go into academia and that's really your only way in. If you're not wanting to go into academia, but you'd still benefit with a doctoral degree from whatever your chosen career path is, then you should set yourself up for the best possible outcome by choosing the program that will best benefit you, professionally and academically. If UC Davis is both of those things (admittedly, I'm not well versed on UToronto's academics), then I would (personally, if I were in your shoes) talk to my family, and friends about creating a self-care plan: set up weekly phone times, visits, email or Skype calls, etc. if it means you do end up going to UC Davis and this will give you a solid way to cope and adjust to the distance. Best of luck to you!

Not sure which section this belongs in. I'm a 22-year-old MA (History) student from Toronto and I've applied to begin my PhD in the same. I'm a dual citizen of America and Canada (it becomes relevant). I've applied to a few universities, but the relevant facts here are as follows. UC Davis has accepted me; it was my first choice, tied with UofT. UofT declined me. I'm still waiting on a reply from uOttawa.
Davis is a great opportunity with some amazing supervisors, and from what I've heard funding can be an issue for international students which it won't be for me given my citizenship. The thing is I've lived at home my entire life and wanted to stay here for my PhD so I wouldn't have to uproot my whole life. I did my undergrad and am currently doing my MA at UofT. The consensus seems to be that three degrees from the same university is frowned upon in academia, though it wasn't such a concern for me because I'm not looking to stay in academia after I get my PhD. Anyway, I was really excited and so sure I wanted to do this. I still am. If Toronto accepted me I would've gone through with it in a heartbeat. I'm just scared right now, for the first time in a long time. It's not the workload that's putting me off; I enjoy that for some weird, fucked up reason. It's moving. It won't even be that bad because I can come back to Toronto after 2 years (coursework + comps). I just can't get my head past the idea about physically being 4,000 km from my family and friends.
So based on this I have two questions. I'm running the same thing by a couple of my profs, though I would like the grad student perspective, too. I would appreciate your opinions.
I. Is it standard to have these sorts of second thoughts about moving?
II. If uOttawa accepts me, it's that or Davis. Academically, Davis is better for me as I am a US historian and from what I've been told, it's difficult to get an academic position as a US historian with a Canadian PhD. However I want to do something administrative with my PhD, though still probably in the States. Given this, do there appear to be any downsides to Ottawa assuming funding is similar-ish? Ottawa is a few hours from home, so I would be a lot more comfortable there.