I'm with Lowpost for the tactical change until you've worked out what it is that makes your ball find the magnetic lake.

Even the best have this mental failing from time to time.

Take Corey Pavin in the 1986 Masters. On both the 3rd and 4th days he eagled 15 only to stick his tee shot in the water on 16.

He spoke to Bob Rotella about it and confessed that he really tried to focus on his target, but at the last second his awareness focused on not hitting it in the lake and, hey presto, H2O.

I must say that his shot on day 4 was horrid (I have the DVD)! It landed in the pond a good 15 yards shot of the bank! Nice strike Corey!

It'll take time to get around your brain box on this one. If you really want to be able to bisect two hazards like trees on one side and water on the other (sounds like our 3rd hole at my course) you're gonna have to learn how to let go of your watery thoughts. Perhaps even purposefully aim in the trees to begin with. Learn what it feels like to hit to that side of the fairway and take it from there.

If your hole is anything like our one, the tee lines up to aim you at the lake, so aiming across at the trees takes some effort!

__________________
Luke: I don't believe it!
Yoda: That is why you fail.