It is interesting to observe testers, especially folks new to testing, consider developers as the "other" group, the one's testers are up against. Some credit for such a notion must go to the organizations themselves for fostering this silo & antagonistic behavior without channelizing the efforts from both groups towards the common goal of releasing a quality product.
While newer methods such as Agile development require testers and developers to be partners and work together as one team, work needs to be done to make needed cultural changes and facilitate smooth cross-functional interactions and team work.
Looking at the relationship between testers and developers, one could probably say that testers exist because of what developers do ! There are many more such statements about the relationship between testers and developers. Here's one more - "If debugging is the process of removing software bugs, then programming must be the process of putting them in" and yet another helpful quote from a developer, "My software never has bugs. It just develops random features"
Producing and delivering a quality software product calls for all involved to work together towards a common goal while realizing that quality cannot be an afterthought or confined to a QA or QC team; quality must be the responsibility of both developers as well as testers and quality must be built into the product.