Well, its been awhile so I guess I should contribute my latest thoughts.
Basically, I have decided I am going to upgrade and buy a better van at some point. I really want a high top. However, I will make sure that I keep the purchase price on the low side... probably a late 90s cargo van with raised roof for around $6000. Since I figure I can sell my current van for about $2000, I'm really only out of pocket $4000 and will still have a substantial amount of money for emergency fund. If I ever need to spend part/all of my emergency fund, I will simply just get a second job and work 60 plus hours per week until I have enough saved again.
My ex and I have put money away every month since my kids were born so their education costs are well on their way. I dont want to sound selfish, but I need to look after myself as well and I dont think its asking too much to allow a person to buy a better home/van in which to live.
Thanks to all who contributed to this discussion. It has been very insightful.