Seriously, if you wear a 10mm metal vest, do you think it will prevent you from getting injured if you purposely jump off a 3 storey building? People who think installing a good AV and antispyware will forever protect them from malware are ignorant. It takes a careless person to get infected too, even if he has the right protection. Besides, you didn't say if you were using the Pro version of MBAM which has that real-time scanning and blocking of malicious programs and sites. And even so, there's no such thing as 100% effective. New malware are created every minute and it takes some time for antimalware to develop a cure.
I've been using MBAM (pro of course) in conjunction with Avast free version for more than 3 years now and never got infected. That is also due to the fact that I don't fool around with malicious sites and programs on my main computer. If I ever have to try those things, I do it on a virtual machine so my main computer isn't harmed.
Lastly, getting infected by 7,978 malware is absolute stupidity, carelessness and ignorance. Don't blame it on your security. It was you who allowed it by trying shady programs and going to malicious sites. Don't you use Firefox and at least NoScript and Web of Trust add-ons to guide you?