
I would be wary of being too 'harsh' on her -
I fully agree she needs to learn to cope with out you - it does sound as if her bond with you is a little needy and unhealthy and that needs to be changed BUT - if you attempt this by 'force', ie, closing doors, shutting her in a crate, you may actually make the problem worse.
Asking her to stay in her crate and gradually building up that period of time, with lots of rewards is fine, stick with that.
With the following you about though I find it is better to have THEM choose not to follow you, rather than you physically prevent it.
How you do it is a bit long winded to explain but makes sense when you get it. You play a game of Simon Says - basically. Sometimes you invite her to come with you, and when you do y ou acknowledge that she is there, fuss, talk to her, odd little rewards. But sometimes you DONT invite her to follow you, and if she does anyway, you ignore her totally. No fuss, no rewards, no talking to her, do not acknowledge that she is there at all.
Be consistent with this, do it ALWAYS but also set up training sessions where for five or ten minutes a couple of times a day, you will purposely NOT invite her, and then flit from room to room - make sure that just as she settles to watch you, you move on again so that in effect it is REALLY irritating for her to keep following, settling to watch you,then getting up to follow again, for absolutely no reward whatsoever.
When you start to get the feeling shes realising this is REALLY annoying, then introduce some motivation to NOT follow you. With most dogs this has to be a VERY high value long lasting reward that she cannot pick up and cart around after you. I usually recommend a large raw meaty bone that is too big to carry around, you could also try an oversized kong, perhaps run a cord through it and tie it into her crate so she cant drag it around.
Then you repeat the training sessions, flitting from room to room, start out by leaving the room for a few seconds, returning and sitting for a minute or two to her room, then off again, and gradually build it up so you are out of the room for the same amount of time you are in it, then out of the room longer than you are in it.
Hopefully then, she will CHOOSE not to follow you, because shes learned if you didn't ask her to come with, its boring, AND she has something better to do anyway.
As for getting on sofas - if you LIKE having a cuddle with your dog, as long as she is happy to get off when you ask her, I don't see a problem with that. What I do have a problem with is you purposely making her stay off when actually you AND she would like a cuddle - to me that sounds like neither of you is particularly happy and you do risk her becoming depressed and confused by it.
Don't get me wrong, if you ask her to get off and stay off, she should, thats sensible. And she should be able to cope with being asked to wait before she gets up because you are busy, again thats sensible. But owning a dog and sharing your life with one should be fun, and from this an dyour other post in many ways it sounds like neither of you is having fun!