Electrical Problems 2000 Silhouette

Hi

I have had a couple of strange electrical problems:

1. My cruise diengages when I turn on the signal light.
2. My brake lights stopped functioning
3. My fuel gauge is all over the place

I checked my lights and I found both bulb ends wher ethey go into the sockets were melted for the brake light bulb only.

I cannot not find problem with cruise control.

Any suggestions are welcome, and any explanaton for melted lights also welcome.