Skipping friends engagement party

So I recently became friends with this girl in my grad program, she's funny and cool and likes alcohol like me lol anyways I was over at her house last week and she told me how she got engaged on Christmas eve (ugh holiday engagements). Anyways she is having a housewarming party soon and of course she wants me to come. It will always be their way to tell everyone about their engagement. Well ok I am thinking about it and looking at the people who they invited.. all seemingly couples. I don't need that in my life especially being that I just lost my relationship like 2 weeks ago and want to die. I was telling my bestfriend and she said I should go and make friends and maybe a couple will like befriend me and want to introduce me to someone which sounds desperate and horrible (not that trolling every single dating site is better). Anyways I RSVPed after I had an awesome date and thought it would be promising but I think I changed my mind, especially since he doesn't seem interested. Idk if I should tell them or just not come or make something up the day of? It wouldn't be so bad if there were going to be a lot of hot single people there or if they weren't one of those overly loving couples... it can be so annoying I just don't want to deal with it. How do I handle this situation?