Why didn't I jump too?

The other night I had dreamed a rather scary dream, for me at least.

Me and Trevor Porter were hanging out before he left on his mission.

I asked if he wanted to go for a drive and he said yes,

so we got in my truck and started driving.

We went to this lake that had big rocks in it(like Sandhollow Res.)

We parked the truck and walked out onto one of the rocks/ cliff things.

We were enjoying the view.

 - Know how in dreams the scene can suddenly turn different and you don't realize it? Well that happened. -

 Somehow it ended up that we were now surrounded by water,

stranded out on this rock in the middle of the lake.

So, naturally, we had to swim back to the other side to get back to my truck.

 I scanned the water to find a good place to jump in,

when I realized there was a gator in the lake!

In a hurry I yelled at Trevor not to jump and showed him what I had spotted.

We had some food with us,

it was a burger and a napkin.

 So Trev got the idea to throw the burger in to distract the gator and then we could jump in and swim back.

 He threw the burger then jumped in afterwards,

 but instead of jumping away from the food he jumped towards it.

I was frantic.

I could see the gator coming for him and had to think of something quick to save my friend.

He yelled at me and told me to do something.

But I couldn't,

 there was nothing that I could do.

 I had the napkin and threw it,

 in hopes that in some way the gator would go for that small napkin instead of my friend.

I knew it wouldn't work.

 I watched as Trevor slowly sinked down into the water.

It was horrifying,

 however the gator wasn't to him yet.

He was drowning.

 I watched as his head went under and the bubbles came up.
I had lost him. I lost one of my best friends. Someone who I truly loved and cared for.

I woke up in a sweat,

 breathing heavily.

 I couldn't believe what I had just dreamed.

Why didn't I go after him?