Yes, I feel the day will come when Swift will be able to keep a boyfriend. Hiddleston was perfect, but not necessarily a perfect match. They are both talented and beautiful, but very different in their personalities and outlook. Eventually Swift will find the right match and eventually she'll be mature enough to figure out what she really wants in a life partner.
Yes, Taylor Swift will eventually keep a boyfriend, and it is wrong for the media to focus so much on her love life. As a twenty-something year old woman, she is simply finding who she is and is not compatible with. It is only right for her to have as many boyfriends as possible before marrying one.
Most people settle down eventually. They find someone they want to stay with or they decide they are content to be alone. Regardless of how long she takes to get there or if she gets there at all, what people should be concerned about is whether or not she is happy, not if she conforms to an ideal.
Taylor Swift isn't different than most girls her age, and it is even harder for her because there is a constant public spotlight on her relationships. As she gets older though, she will learn how to deal with it better, and to pick boyfriends who are better able to deal with the constant scrutiny.