Tessa is the same way and we got her at nearly 4 mo of age. In the beginning she'd cry and howl and get frantic if I was out of her sight. Now she just whines a bit
I do allow her to follow me around the house, I wanted a companion dog and I'm OK with that...plus I get to keep an eye on her so it's all good!
She used to cry in the crate too but I began feeding her meals in the crate plus when I was home I would put the crate next to me with her in it and occasionally give her a treat telling her what a good dog she was (this only worked if I was sitting next to her, not if I was moving around the room) . Now anytime I put her in the crate (bedtime and when I have to leave) I give her a small piece of chicken liver. This is the only time she gets the yummy liver so she began associating her crate with something good.
Tessa also sleeps in our room in a crate.
I also say "I'll be back" in a very matter of fact voice when I leave. I also say this if I have to go upstairs where she isn't allowed yet. She still whines a bit if I go up there briefly (like to get something...I never go up there for an extended time and leave her downstairs) but she no longer panics. She no longer cries in her crate when I leave.
It has gotten much better with time (we've had her for 2 months). She still prefers me and always will. I'm now used to having a partner when I go to the bathroom, shower, etc, lol! If my DH is home with her while I'm gone she will now play with him but then she will go to the door I left from and sleep on the rug until I return. But she no longer cries so that's progress. If we're both home she will stop whatever she's doing, even if it was playing with DH, and follow me if I get up and leave the room.
That part I can live with and we just let her follow me. I was most upset about the crying and howling if I left her...after all, I have to sometimes leave the house!
I spoke with an animal behaviorist about this and this is what she told me to do: tether her to a chair, doorknob, whatever, or crate her (we did this exercise with both), and say your key word or phrase you will repeat every time you leave. Leave the room and as soon as she begins to whine whip around and very sternly "shush" her. This startled her enough to stop whining, even if for just a second, then praise and treat. Gradually increase the time away and be sure to praise and treat for her silence even if it is just for a few seconds. Keep coming back and eventually they learn you WILL return.
I tried the chewies or kongs but she won't have anything to do with them if we're not home. I do take her out of her crate as soon as I get home but I don't make a huge deal over it.
I don't know, one day it just clicked and she just realized that if she goes to her crate during the day I will come back and it's OK. She usually naps while I'm gone so maybe she likes it, she's usually too busy following me around to sleep for long during the day, lol! And as I said, I just let her follow me around if I'm home. We do try extra hard with bonding time with DH. If we walk her DH sometimes takes the leash and even though she'd rather be beside me we don't give in and we tell her what a good dog she is, he has special games only he plays with her (usually roughhousing which she loves), he feeds her when he's home, brushes her, takes her potty (although at first I had to go out with both of them, now he can take her alone)...etc.
Sorry this is so long.....Good luck and believe me, it will get better, just hang in there!