Why there can only be one God...

I'm back on the big bumbling buffoon that is the PC, our electricity went out the other day ( reminds me of the good ol' days in Pakistan) when it came back on the wireless thingamajig had a blown fuse so the Internet on my poor ickle laptop doesn't work (sob,sob, sniffle, deep dramatic sigh).....
Anyway back to the topic in hand, I've started these online Aqeedah/Tawheed lessons run by the middle way sisters. It's really good because you can decide the time to suit yourself and you can do it in your pyjamas if want to :D. I had my second session yesterday and the sister was giving arguments as to why there can only be one God. I found them to be so logical and commonsensical that if i didn't believe in one God already they would have converted me on the spot, so thought I'd share them:)

(WARNING: the following text is VERY deep and took me a while to get my head around it so you may have to think about it for a while before the penny drops)

• Whatever God wills happens, therefore if there are 1+ Gods and one wants something to happen whereas the other doesn't then what happens? either one will get their way thus the other is not a God as he cannot do as he wills, OR both will happen..but how can two opposite things happen at once?! OR none of their wills will occur thus making them both unable to execute their will, therefore neither of them can be God
• To be able to distinguish between the 1+ Gods there needs to be some difference between them, otherwise whats the point of having more than 1 if you cant tell them apart right?! BUT for them to be different must mean that they have different attributes, yet God has only perfect attributes, THUS one of them would probably have attributes that aren't perfect, so how can they be God if they are not perfect in every way
• If one God is sufficient enough to manage the worlds then what is the need for the other one? If one God is not sufficient enough to manage the worlds and another God is needed then neither of them can be Gods as they are needy and dependent on each other, whereas God is in need of nothing from no one (double negatives and alliteration:))
• If there is 1+ God then each of them should be able to hide things from the others , if they can then the other Gods are unknowledgeable as they are not all knowing (therefore they cannot be Gods). If they are unable to hide things from the others then he cannot do as he wills and thus is incapacitated
• If there are 1+ Gods with equal amount of power then the summation of their power must be stronger than each of their powers alone, therefore making the sum of their powers more perfect than each Gods individual power. THUS this suggests that on their own the God wasn't perfect in the first place which is impossible as God is perfect and without the need of anyone. (Partnerships and associations are a sign of imperfection in them selves, as it implies a need for the others in the partnership)
• If there is more than one God then perhaps one is able to "buy" the other one out and remain the only one in power, if so then the other one is weak (yet weakness isn't an attribute of God?!), If none of them can "buy" the other out then are they really God as they cannot do as they will..........