Am torn on that one MoH...
When H and I were back together after first finding out about his affair, it was an important birthday for him and I spoilt him rotten. Got him some really beautiful gifts (that I couldn't really afford).
My thinking at the time was exactly like you MoH - make him see the sort of things he'd be missing if he wasn't with me, make him appreciate the things I do for him and the thought that had gone into it etc...
And I do think it had that effect. For about 10 seconds. I think it made him feel guilty, appreciate me, and love what I'd got...
However, it didn't stop him for one second! I popped to the hairdressers (in anticipation of our night out with surprise limo that I'd planned...) he left ds with his parents and sneaked off to see OW while I was safely out of the way
So I tend to agree with Dior now on this one.
(Although I fully see where you're coming from and you should most definitely do what feels right for you.)