I've had the same problem recently, not so much the size as it appears, but folks complaining that it takes too long to load 3MB photos, but the cure is just the same - resizing before uploading them.
I don't use photobucket or any other similar remote photo websites, so I save them to the laptop from my devices. From there I use "Microsoft Paint" which although each photo has to be reduced one at a time, is fairly quick and easy to use.
Reducing photos is a mystery to some, so if you don't know what I'm on about, open the file in "paint" and select "resize" and depending on the pixel size of the original, select a percentage less than 100% whilst maintaining the aspect ratio.
For example, a 3MB photo file reduced down to 40% will return a photo file size of appx 1MB. It seems to vary a lot so I suggest you play with it first to get a feel of what you're doing and the results you get.
There is a variety of software packages that do this, in many different ways. I use paint because it's already on the platform.
Anything over 500 - 600kB is big enough for forum purposes, unless you want to zoom in on detail....