Currently I'm into collecting manga. I have no idea how many I own, but it's a lot. I keep my favorites in a wicker bookshelf that my mom gave me.
I have dozens of volumes squirreled away in various corners of the house; I wound up overwhelmed by them because I would buy about 5 volumes per series at a time. I was always afraid that I would go crazy if I were left at a cliffhanger or something.
That changed when I bought Nurse Hitomi. I was forced to buy only the first volume because that's all there is that's currently been translated into English. I read the volume, enjoyed it, and to my surprise, I wasn't upset at all that I have to wait a little while for the next one. Now I only buy the first volumes of series that sound good to see if I'll actually like them. That way I don't feel guilty if I spend money on something that wasn't my cup of tea, since manga on Amazon only costs about $11 per volume.
Another thing that I wound up eventually realizing is, I don't have to be completely obsessed with a series in order to enjoy it. I used to buy manga (once again, 5 volumes at a time) expecting to develop a special interest in a specific series. I expected this to happen because that's how I used to be about anime when I was a teenager- I used to zero in on one or two specific series and obsess over them until a shiny new series came along.
When I tried this approach with manga, I always wound up disappointed, because I wasn't really in it for a nice story, I was in it for a very narrow obsession that would consume my every waking thought. Eventually I realized that I was into it for all the wrong reasons. Most people don't pick up a book and expect to be completely obsessed with it; most people will pick it up and simply expect a good story. Once I began taking that approach to manga reading (combined with my approach of buying only one volume at a time), I became much more satisfied with my hobby.
Sounds like common sense, I know, but common sense is something that tends to eludes me until I learn it "the hard way".