Recently me and my best friend have been arguing 24/7. We used to be eachothers only friend for about a year but recently we've become friends with another group of people. She's now going out with one of them and we get into arguments most days. It feels like now that she has a boyfriend and other friends she has no need for me at all. I've also been diagnosed with depression not too long ago which is making this even harder on me. What should I do?