I second the Five Love Languages. The basic premise is that people receive (and therefore, usually give/show) love in different ways - I think the book identifies physical touch, words of affirmation, acts of service, quality time and gifts as the most common ones.
It's rare for two people in a couple to both have the same primary love language so you can get into a situation where you both feel like you're trying really hard and the other person isn't appreciating your efforts, but if you're not showing love in a way they feel it then they won't "hear" you if that makes sense.
For example, my primary love language is physical touch but my husband's is words of affirmation. If he told me all the time, "I love you so much, you're the most beautiful woman in the world, you're my favourite person ever, I think you're wonderful etc. etc." I would just be thinking he was using words to cover up for a lack of affection because if he REALLY loved me he would hug me. Similarly if I held his hand, squeezed him when I went past him and gave him foot rubs he would be thinking that I couldn't REALLY love him because if I did I'd say it! So now I make an effort to tell him when I think nice things about him (I used to think them but not say them out loud because I thought he knew! But it's important to him to hear me say them) and he makes an effort to be physically affectionate (note: this is not a sexual thing, that's separate
). My husband's secondary love language is physical touch so that does tie in nicely with me and his is quality time so I try to make sure we have time regularly to focus on each other, even if it's only a few minutes after the toddler is in bed. (Her top two seem to be words of affirmation and quality time.)
I enjoy quality time with people and acts of service has become much more important to me since we had a baby but gifts I could take or leave, I don't seem to attach emotional significance to them but my MIL does so we always try especially hard with her birthday presents and so on.
It's quite an easy way to improve the way you relate to one another if you're both willing to make an effort. The book explains the different types and then there's a questionnaire to identify your own.
Other ideas: would he find communicating easier on a walk outside, or via letter to each other?