Hey Krunchy and welcome.
It sounds like your husband had what's called a "victim puke". Basically he's been bottling things up for a while and something seemingly minor has caused him to lose the plot and take it out on you in well a vomit of rage... Generally they're not an advisable way of going about things and not nice for you, however you need to look at why he did this, which you've done. In his mind he appears to be genuinely concerned about what's going on in your life and he does things like sending you flowers when your upset. Your reaction obviously was not what he expected and I'd say similar episodes have built up to this morning's little episode.
Now I'm no mental health professional but your issues with self worth and difficulty accepting gestures with seemingly good/nice intent is something you need to address with a professional (I'm not sure if you have done so already?), because ultimately you will lose your husband or like you said he'll have an affair.
The good thing is that you are actually aware of how you are treating your husband, next step is to do something about it. I'm not saying at all that "it's just you" - there are always two sides to any relationship, however talking to a psychologist about these things would be a good place to start.
How did you resolve the incident with you husband this morning? Or didn't it resolve?
On a bit of a tangent, there's a book called the 5 Love Languages (you can get it electronically too) - might be worth finding out what his love language is and speaking that to him??