I also have a 2002 Forester, which has 165K on it and never needs any repairs, only regular maintenance.
I also drive a 1989 Mazda B2200 with 225K, but the engine exploded right at 200K, so all that stuff is fairly new. It still looks old and has none of the features of a more modern vehicle.
There's something to be said for increasing your self esteem by owning a new car, but the monthly expense always scares me away. You must also remember that new cars do not have immunity from repairs or maintenance, which is additional to the monthly payment and increased insurance.
One thing you could do is take your car to a trusted mechanic (I'd try to avoid the national chains. They tend to want to upsell everything) and have him/her give it a complete inspection. Although he won't be able to predict failures, he will be able to tell what is going to be an expense in the near future. Usually this will cost less than an hour's labor and will give you an itemized list in order of importance of upcoming costs.