1JZ Experts, please look! Head Gasket Woes

[DrftKingIII]

I'd like to get a bit of insight from someone with a bit more knowledge than I. Here is what happened:

1JZ, mostly stock except intake/exhaust/FMIC/EBC. The car has been blowing a heater hose off, the one that wraps behind the head from one side of the block to the other. It's blown off a total of 4 times now, all under cruising conditions/out of boost. Previous owner had a metal tube on it with no flared ends and crappy clamps. It is now fixed.

This past time, I was on the highway doing about 60MPH and it blew off. As soon as I heard/smelled/saw that it came off, I instantly shut the car off and coasted it off the highway onto a side road. I managed to get it back together and fill it with distilled water enough to limp it 5 miles back to my house. I did notice on the way home that my AFR's were almost constantly maxed at 16 all the way home. I fired the car up for the first time in two weeks yesterday and topped off the coolant/water and it was idling between 12-13 AFR's. As soon as the thermostat opened and the car was starting to warm up and the idle dropped, I checked the AFR's and again, it was maxed out at 16 just at idle, so I shut the car off. The first three times the heater hose blew off, after I temporarily fixed it and moved the car, the AFR's were fine. Thinking this last time was the final blow on the head gasket, but wanted some more experienced insight from someone who may know.

Let me know what you guys think!