I'm so sorry that this is so long. I, like many other woman here, was in the same situation. My boyfriend of 7 years has always struggled. He's shy and terrible at talking about his feelings ( in a confrontation, he literally feels nauseous). I almost gave up a few years ago and here are some things that have helped us out tremendously. 1. (His suggestion) making a love box; includes date ideas, gift ideas, places I want to go/see, things I'm insecure about, my favorite anything (flowers, candy, color, etc...) - reason: he WANTS to do kind things for me but when the time comes, he draws a blank (much like studying all year and panicking during the test). This box gives him a peek at my brain. It gives him time to understand the way I think. Having me write down important things helps him remember what I like and gives him a "head start" when doing something kind for me
Communication, communication, communication -reason: he's terrible with picking up nonverbal cues. Nonverbal cues are no longer allowed in our home because they will never be picked up. Something simple to me is a Rubik's cube for him. Monthly, we talk about how we feel (sometimes 5 minutes, sometimes 5 hours). We talk about things we feel are neglected. I ask him how he's doing and what I can do better and he does the same. The defining step in your next few days will be his and your willingness to communicate.
Giving up the idea of spontaneous flowery showers of love
reason: with my boyfriend (who sounds much like your boyfriend), the thought of doing something extravagant in the name of love is incomprehensible. He's stable, he's dependable, he's warm and kind. My idea of flowery showers of love has adapted so much over the last 7 years. Before, I would've wanted a private beach trip with horse back riding at sunset. Now, I realize that every single time I get out of the shower, I lay my head in his lap and he pets my hair. For hours. Sometimes I fall asleep. Before, I wouldn't have considered this a grand gesture but now this is my idea of affection. This is my tier 10 of love. And he does it gladly every single night.
OP, I don't want to say that the way you feel is invalid because I have been on the receiving end of the same situation and it is valid but as much as you want to help him learn more verbal/physical affection towards you, I hope you will adapt your ideas of what the term affection is. He could be giving you peaches while you're asking for apples. Both are fruit, but only one is interesting you right now (or so it seems).
My heart is with you at this time and I hope you find the love and affection you crave. It is beautiful to love and be loved. If you'd like to ask anything specific, I'd love to talk.