Remove any copies of Java 8 on your computer, also how much memory are you assigning in the launcher?
This thinks you only have 1.2GB free however that may be due to it picking up that 32bit Java 8 copy
[23:02:58] [DEBUG] LaunchFrame.main:219: FTB Launcher CI Build #: 203, Git SHA: 9b3092c84c648524d65019efecfa000588d7773e
[23:02:58] [INFO] JGoogleAnalyticsTracker$2.run:484: AnalyticsBackgroundThread started
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:33: FTBLaunch starting up (version 1.4.3 Build: 10403)
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:34: Java version: 1.7.0_72
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:35: Java vendor: Oracle Corporation
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:36: Java home: C:\Program Files\Java\jre7
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:37: Java specification: Java Virtual Machine Specification version: 1.7 by Oracle Corporation
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:39: Java vm: Java HotSpot(TM) 64-Bit Server VM version: 24.72-b04 by Oracle Corporation
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:40: OS: Windows 7 6.1 (64-bit)
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:41: Launcher Install Dir: C:\Users\Majeski\Downloads
[23:02:58] [INFO] LaunchFrameHelpers.printInfo:42: System memory: 1267M free, 3796M total
[23:02:59] [INFO] JavaFinder.parseJavaVersion:166: The FTB Launcher has found the following Java versions installed:
[23:02:59] [INFO] JavaFinder.parseJavaVersion:168: Java Version: 1.8.0_25 sorted as: 1.8.0_25 32 Bit Java at : C:\Program Files (x86)\Java\jre1.8.0_25\bin\java.exe
[23:02:59] [INFO] JavaFinder.parseJavaVersion:168: Java Version: 1.7.0_72 sorted as: 1.7.0_72 64 Bit Java at : C:\Program Files\Java\jre7\bin\java.exe
[23:02:59] [INFO] JavaFinder.parseJavaVersion:168: Java Version: 0.0.0_00 sorted as: 0.0.0_0 32 Bit Java at : C:\Windows\system32\java.exe
[23:02:59] [INFO] JavaFinder.parseJavaVersion:168: Java Version: 1.7.0_72 sorted as: 1.7.0_72 64 Bit Java at : C:\Program Files\Java\jre7\bin\java.exe
[23:02:59] [INFO] JavaFinder.parseJavaVersion:194: Preferred: Java Version: 1.7.0_72 sorted as: 1.7.0_72 64 Bit Java at : C:\Program Files\Java\jre7\bin\java.exe