<human>: Could you distill the essence of the text into 1-3 sentences?

About a week ago I hauled my horse to a competition with my lovely 20 year old F-250. I love this truck dearly but am quite a novice when it comes to the maintenance of a hauling vehicle, especially an older one. I had planned on getting the oil changed and fluids checked but spontaneously decided to go on this little field trip first.

Fast forward to the afternoon when it's 95+ degrees and I am on the freeway and it starts making a weird clatter anytime I'm on the accellerator. It also seems to have less power and the engine light comes on. I have no option but to get the horse home due to the insane heat, so I drive a little slower and we make it safely back. Park the truck and it won't start. Call my neighbor for a rescue but while waiting for her it turns over and I (STUPIDLY) decide to just cowboy it home since "getting it towed from halfway home will be a lot less of a hassle then getting it towed from 20 miles away"

Well turns out I had run out of coolant, blown the head gasket, and have completely, utterly ruined the engine completely. The shop just called and said they can get a rebuild with a 3yr warranty from Ford (it's a 351 Windsor) so I would essentially get an entire new engine, water pump, hoses, whole 9 yards.... To the tune of $5-6k. I paid $4300 for it. I'm moving to Florida from California in 6 weeks and was planning on selling it before the move.

I feel sick over it, should have checked the damn coolant before hauling in the heat, should have taken it in for it's oil change, should have just stayed in bed that morning.... UGH.

Now I'm stuck between a rock and a hard place and don't know whether I should get the new engine, keep the truck, drive it to Florida with the brand new engine.... Donate it to charity and learn my damn lesson.... Or something else. I have a CL ad up to see if anyone wants it as-is but haven't really had any serious interest yet.
<bot>: TIFU by being a complete newb at dealing with engines, and essentially totaled my truck moments before selling it and moving across the country.