Merging Two Internet Connections in Windows7 and Sharing via Wireless

Hello everybody!

I have two separate internet connections (both wireless - each connected with an USB wireless adapter) and I would like to share them to my other devices in the house via the laptop`s integrated wireless adapter. I am using W7x64 with a clean install and HP hardware with no conflicts or errors.

I tried bridging them and sharing the network bridge via Connectify but this only aproximately works (quite bad like all the 3rd party software solutions) when both networks are connected, when one fails Connectify stops working and crashes.

Is there any way I can do this using Windows only or any other solution that does not imply Connectify or changing the OS?

I would not mind have load balancing, but I`m not even considering that at this point, I would like only
to be able to use both, in a failsafe manner, since either one or the other have the habit of randomly disconnecting at times.
I red aproximately all that was to read on the net about this, not much info, and most results lead my steps to purchasing Speedify, thing I am absolutely against!

Thanks all for patience, any solution will be greatly appreciated!

The laptop has also a wired connection and I have a wireless router around (D Link DIR 615), if there`s a solution so I can merge both wireless connections and send them to the wireless router to make them available at the same time to all the clients via the router`s wireless, that would work too.