I prefer the syringes over the pens also. I find sometimes when I use the pen the medicine runs down my belly if I am not holding it at the right angle yet it looks perfect. My syringes are prefilled, I didn't know until reading your post that you can get the medication separately. I would check to ensure that if there is more than one dose of Humira in the vial that you can keep it in the fridge and use it next time. I know with my MTX you can only use the vial once then throw the rest away. All the best to you on Humira.
Aimee, perhaps your friend's wife used Enbrel for her RA, which is also an anti-TNF drug, similar to Humira. You can get Enbrel in a form that you mix up yourself, without preservatives. The prefilled syringes and auto-inject forms of Enbrel also sting like the dickens; maybe that's where your scientist friend got confused.
Unfortunately, the one and only study of Enbrel for Crohn's showed questionable benefit, so Enbrel isn't prescribed for Crohn's. But I do know of some IBD folks who use Enbrel for their arthritis, and they say it helps their IBD as well.