Games at a loss

So yesterday we went to the west Ed mall again and I played a game of warhammer 40k. And I lost by a single point. Now not to lead you astray, this was in no way a close match, I only had 2 models left on the board -thank khaine for leadership 10 or they would have ran away- and they were surrounded by tanks, guard and a vendetta. So basically what happened in the game was I infiltrated my rangers into the stupidest place possible, not that it wasn't the second best place for them, and they died first turn. I placed my dark reapers in a good location and took out half a squad of guard, and they died after the hellhound was finished with my pathfinders, god I hate flamers. Just the turn before my reapers died my wave serpent came in with both my farseers, you can look at my list below, and a squad of dire avengers. The wave serpent did nothing but my farseer was able to immobilize a chimera (one of three). After my reapers died the wave serpent was immobilized and my war walker came in, shot the living daylights out of the back of a tank and did nothing whatsoever. When I deployed the squad inside my wave serpent I thought hey I know I will spin the tank with eldritch storm and take some shots that will do some damage, but it spun to face me instead, making it so that my shots were totally useless instead of more useful. Then with everything else dead the only reason why that squad survived was because of the spell fortune saving the models again and again. And in theory I could have moved my squad on top of the objective but to do that was to move closer to a vendetta, and it was turn five I didn't think the game would end, I was wrong.
My list (1000)
HQ
Farseer(55)
Doom(25)
Fortune(30)
Runes of witnessing(10)
Spiritstones(20)
Total(140)

Farseer(55)
Guide(20)
Eldritch storm(20)
Runes of witnessing(10)
Rune of warding(15)
Spiritstones(20)
Total(140)

Troops
Dire Avengers x10(120)
Exarch(12)
Twin Shuriken catapults(5)
Bladestorm(15)
Wave serpent (90)
Twinlinked Bright lance(45)
Total(287)

Rangers x5(95)
Pathfinder upgrade x5(25)

Heavy support
Dark reapers x5(175)
Exarch(12)
Tempest launcher(20)
Fast shot(20)
Crackshot(10)
Total(237)

War walker (30)
Scatter laser(15)
Eldar missile launcher (20)
Total(65)

On the upside the weather has been nice with storms every few hours, I like rain thunder and hail mid summer, it makes me cheery.