First of all well done on being clean for a year and four months what an awesome achievement. I am sorry to hear that you feel your depression coming back. Do you have any support at all for your depression? It can be so important to have support to enable us to get through it.
Also one of the things that often slips when we are feeling depressed is our self-care so things like personal hygiene, eating habits, sleeping etc tend to suffer. It is really important to try and keep up basic self-care though as not looking after ourselves can contribute to the depression. You may feel that you don't deserve self-care but everyone does and this is the most important time to try and maintain at least a little bit of it.
As for the self-harm, try and remember just because you are going through a rough patch doesn't mean you to give in and relapse. Think of how hard you have worked to get to where you are and use that as a motivation to fight through the urges. You may also find it helpful to have a list of coping strategies on hand somewhere easily visible so if you do get the urge you can work through a list of strategies. There is a great list of distraction ideas that can be found
here that you may find helpful to give you some ideas of things to add to your list.