Aftermarket high quality mounts

On my last bike the mounts snapped the frame in half where they were, and also broke earlier than that.

Any decent mounts that I won't drill the frame? Or is it better for the front

Were you using any rubber in your mounts? That's a no-no.
We always try to discourage drilling a frame to mount an engine. That's just asking for trouble. Also the engine should be mounted as solidly to the frame as possible with good/total contact between the frame and the engine mounting surfaces.
Some photos would be helpful as well as what frame material, steel or aluminum and how your mounts fit the frame.
Tom