Putin is an ex KGB, so what's really in his mind I guess no one can predict. There are high and lows in every relationships, but does that essentially mean all relations end up in a divorce ?? NO.
Regarding America, well I will take your word for that. Who better than Pakistan can enlighten others about who America treats her allies. ??
And FYI, we are not pouring in much, rather the Americans are Chinese are pouring in a lot of money into our economy. Indian investments in both America and China is negligible compared that what they invest here.