Absolutely. There was a study done several years ago showing that lack of sex does not necessarily mean the couple has other serious problems in the relationship like previously thought. The common belief was that lack of sex in a marriage was a symptom if a greater problem. This is sometimes true, but there are many couples who have a loving, bonded, relationship and rarely or never have sex.
Both people have to be ok with it. I do think a great sex life is a great thing and adds to a relationship. My husband and I have had to go through months at a time of no sex and I miss it, and I feel cheated out of it, and I think it negatively impacts our relationship, but not so much that it destroys our closeness, unity, or enjoying so many other things.