Apologies in advance this could be a very long one.
My cousin, who I used to be very close to, was in a bit of a difficult situation around 6 years ago. Her boyfriend had been kicked out of his house and they were sleeping in her car as her parents wouldn't have agreed to let him stay there. So as I had a spare room in my house I let them love with me, paying rent. I really enjoyed living with her but the boyfriend was an utter waste of space. Spent most days getting up late, bumming around my house, playing guitar and smoking weed (not inside). He couldn't seem to hold down a job and she was paying for everything for the both of them. I just felt really uncomfortable around him as he very rarely speaks. I work full time as a busy teacher so had other things going on in my life and my exh also moved in a few months after they did - so there were 4 of us.
Exh and I went on holiday about 6 months into this whole arrangement and upon our return I noticed around 90 DVD and blu-rays had gone missing + games etc from the study. Things had been rearranged on the shelves to make it look full up, but stuff was definitely missing. I asked them about it but they denied all knowledge. We had a sneaky suspicion it was him but at the time had no proof.
A couple of days later, while they were out exh went though their stuff without me knowing and found cash converters receipts hidden in pairs of his socks. We immediately handed the evidence to the police and he eventually admitted it and handed himself in. I kicked them out, felt awful for my cousin (even rang her mum ahead of doing it to try and ensure she had some support). He was fined £1000 by the court but as he didn't work was only expected to pay back £10 a month. We recieved money for a few months then it dried up completely. The money was awarded to exh as most of the stuff taken was his, so I never saw a penny and he didn't challenge the fact that the payments had dried up. I continued to be on good terms with my cousin and even found out that he'd stolen money from her by using her debit card without her knowledge.
Cousin and arse split up for a while but eventually he apologised to her parents (wtaf) and they got back together. They've been together quite a while now, but I avoid him at family events. He's now in a stable job and they've just announced their engagement and they're expecting a baby.
I know I should probably just get over it, but hearing everyone congratulate them and act like nothing happened is now really getting to me. I keep remembering that feeling, like when you've been burgled, of when someone's been though your things and taken them.
I just can't forgive him or forget. He's never apologised to me and I just can't bring myself to be happy and congratulate them. Of course I'm pleased that my cousin is happy and she'll be a brilliant mum. But I can't lie. I can't sit there and watch her marry the twat and be pleased for them.
So come on Mumsnet give me a dose of common sense and tell me I'm being unreasonable. It might help me get over myself and be happy for them.