If the engine is not kept REALLY COOL, the heads tend to warp slightly, and then you pop head gaskets easily.

If the head's been over-heated a few times it will likely be warped, and until that's corrected, you'll pop head gaskets easily.

If the engine has been overheated many times, it's possible the block's upper surface is no longer flat, and the block will need to be "decked", or levelled, or else you'll pop head gaskets easily.

Get the hint??

These 2.6's really, really need temp control, and that means a well maintained healthy rad, cooling fan, thermostat, coolant, etc, etc. Once the gaskets start going, the only real fix is to fix the problem, and that usually means block decked, heads shaved (or replaced), replacement rad, etc.
Then they're fine.

Hope it's not as serious as it could be............