It sounds like your boyfriend's got a lot of Valentine's Day-related scars! If the day is important to you (which is totally valid!), it's worth sitting down with him and asking if he's comfortable celebrating with you, even in a small way. And keep in mind that you don't have to acknowledge the day in traditional ways: if he doesn't feel like going out for Valentine's Day or making a big deal out of things, maybe you can have a cozy evening in, cooking dinner together. Or maybe you can designate another date your own personal Valentine's Day, if he doesn't want to celebrate on February 14 (it'll be way easier to get a restaurant reservation then, anyway!).