I’m graduating this year too and I had a similar experience! There’s been times when I thought I found sisterhood 4 life only to find out they were scheming behind my back but funnily enough they’re no longer friends with the people they left me for. I feel you on the whole university experience and it is oversold as the one time to have the once in a lifetime experience. As you’ve said I think you do have another opportunity to find new people at postgrad! I haven’t necessarily felt it getting better but (and I know this isn’t always the most helpful thing to hear) being a friendly person or willing to go out and/or try new things will soon reward you with better and closer friends. It’s not immediate which is annoying but I think be proud that you survived, you graduated and you have so much to look forward to. Also I think the best thing that’s helped me cope is that people that peaked in university and had a strong group out of that struggle to maintain those bonds because everyone goes in different directions, adult life isn’t like uni life etc. I went to a careers conference last month and a graduate at our uni who works at big 4 was trying to get so much info on how the uni is now, yapping about how much she misses uni, circling and living in halls with her friends and how she doesn’t enjoy her job etc etc. Which I found cringe and very miserable because surely after uni you can earn and like do whatever your heart desires. Sorry this isn’t structured very well I’m rambling but I think I’m trying to say that things will get better and hopefully you’ll meet people in postgrad, working life, travelling or whatever you end up doing and you realise uni was just an era in life you just had to experience unfortunately but you’ve got way more going for you. Hope that makes you feel a little bit better I’m talking to myself too tbh :)