Sims 3 Max Memory Used, Continuous Crashing HELP!

I have been encountering issues recently when creating my monster mansion in the sims 3. It's a rather large house with a lot of content inside and it seems that recently I cannot play more that 10 minutes without the build/buy mode bar blacking out. This happens when the game reaches about 3.5GB RAM use. Sometimes, I can rescue the game after this happens by going to edit town mode and saving, but then it will quickly go black again and I have to repeat the process. Additionally, after about 3 of these hurried saves, the game will crash mid-save or while building. 

I have already done the DEP for the sims, and LAA. Additionally, I play in windowed mode with no other applications open other than task manager. 

I do have quite a bit of cc, all the expansions, and most of the store; but I would like to keep playing with all of this as it makes the game especially when building. I am also building in IP if that makes any difference.

I have a wonderful computer that I built specifically for playing the sims.

8 GB RAM

Intel i5 4670K processor

2GB NVIDIA GeForce GTX 660 Ti graphics card 

Windows 8.1 64-bit

With a computer like this, how could sims be constantly crashing? My crash long tells me "Max Memory Used, Consider lowering settings." But, why is this? I understand sims 3 can only utilize 4GB RAM and then goes to virtual memory after that. In my crash log it says that I have 4095 MB total virtual memory and 71 MB free virtual memory. Could it be that the game needs more virtual memory to run this mansion? If so, how do I give it more? Or is it something else?

Please help! I've been building this house for months and I can't wait to play, but it's taking forever to build with all the crashing!

Edit: placing my DxDiag below.