Well, I think pretty much everything you mentioned there apart from the peeing is normal for chihuahuas and some other dogs in general.First off, let me say that I do not dislike chihuahuas or dogs in general.
That said let me explain my situation a bit.
I got married about 8 months ago (28M, 33F). My fiance has a 3 year old chihuahua, Pete. I knew she had the dog but we did not live together before getting married. I have never been much of an animal person but from what I saw of the dog I did not thinking sharing a house with him would be too difficult.
I was wrong. For the past 8 months I have tried everything to come to terms with the fact that this dog will be in my life for a LONG time to come. My wife adores him, calls him her "son". We have spent a lot of money to get him trained and it got better but he is still so willful.
1. CONSTANT following, staring, being underfoot when she is not there.
2. Does not listen, very stubborn.
3. REFUSES to poop or pee in the cold, the instant we let him in, he goes.
4. Constant jumping in my lap, getting hair all over me. I am mildly allergic too.
I could go on and on. I guess what I want / need to know is how can I get the dog to understand that I am to be left alone? I have never and would never mistreat the dog but I really do not want to be my wife's stand in when she is away. I have discussed these issues with her and she cannot get past the fact that some people are just not animal people. I really cannot stand the constant following, lap jumping, etc. He even tries to get into the bathroom AND shower when I try to use them!!!
Please give advice on I how I can co-exist with this dog. What I want is to have minimal interaction.
They always follow you because they are people poochies and so you do need to watch out where you step because they are so small.
Chihuahuas can be stubborn, but they DO learn and listen with persistence and training
The hair shedding is also normal and unfortunately can't be stopped, but if you brush them daily they shed less.
As for the peeing and pooing, I have puppy pad trained my ones, so they know where to go at home so maybe you can give that a go.
But when you chose to marry your wife, the chihuahua came as a package and you should just try and love it too because its part of your family now.