I dont understand abusive relationships?

You are correct - staying in a relationship where you can be physically attacked, shows a distinct lack of self-preservation. And that is our biggest et as mammals. Some people are attracted to this type of person because they grew up in a household in which it was the norm, and they thiink they know how to handle it from that previous experience. Some people get fooled - the other is on their best behavior for awhile and then the abuse begins slowly, but builds. Those people are the ones most likely to stay because they remember how it used to be, and they convince themselves that it can be that way again. Some people are so thrilled to be in any relationship that they put up with behavior no one else would, because they are very desperate and can't picture a different future. If the abuse continues long enough, some people get depressed and don't have the energy to get up and get out. And sometimes it is finacial - one partner simply doesn't have the resources to leave - nowhere to go, and no money to get there. Hope this helps:)