What lenses should I add to my nikon D90?

So I recently ask about upgrading my gear or new lenses… So the answer is I'm getting new lenses! I have a nikon D90 a 50mm 1.8d and a SB 400… Ok so My dream lens would be the 17-55mm… I asked a great friend who is an amazing artist and she suggest the 85mm… So Should I add the 17-55mm and the 85mm and later add the SB800 OR should I go with the 18-105mm, the 85mm and add the SB800 now? I would be using it for events, portraits and outdoor sessions, but the reason I'm considering the 18-105 is because it offers me the flexibility of going on family outings (trips to disney and sight seeing) with out changing lens? What is smarter? Any other lens that you can suggest that will satisfy my needs? I'm only interested in NIKON gear NOT tamron or any other, is a just my perference! Thanks to all

Added (1). I want to be able to a better job at events, formal receptions and portraits… I'm not into landscaping, not at all! I rather captive the beauty in people or capture moments that make memories… Thanks

You really need to tell us what subjects you want to shoot with your new lens.

If you are into shooting landscapes or architecture, then the AF-S 10-24 mm may be the lens for you
Macro? Look hard at the AF-S 105 mm f/2.8 macro
Sports, action or wildlife? The latest AF-S, FX 70-300 mm lens is excellent.
One lens solution? The AF-S 18-200 mm VR

Nikon 85mm f/1.8D AF Nikkor Len definitely the best fixed focal length lens I own. It is great for face portraits and a narrow depth of field. An 85mm is a must for any photographer shooting portrait work with super fine detail. The 1.4D is amazing as well, but more expensive.