Can a couple overcome having no sexual chemistry?

I think a couple can overcome having no sexual chemistry but it depends on the couple. For example, some people are asexual so do not (mostly) want to have sex, and they can have successful relationships. Similarly, a lot of people would say that sex is not the important part of a relationship, placing more importance on intimacy, communication and trust. Sexual chemistry may also develop as time goes on so I wouldn't give up hope yet.

Yes, if you have good alternatives and you both agree on the decision it can. But you probably have to do a lot of compensating. Unless you want children, sex is about fun and pleasure and strengthening the relationship. You can get that from other things too, though not always at once. Do lots of fun and different things together, things you both enjoy and that brings you closer emotionally. Like reading a book together, dance, take walks, go to cinemas etc.