In general, masturbation is completely natural and can even enhance partnered sex. It gives us a chance to fantasize and experiment with what works for us, physically. Things can really heat up when a person brings the knowledge they glean during masturbation to the bedroom. As well, there is always the opportunity to incorporate masturbation into partnered play… Have you considered asking your partner to watch you masturbate?
Alternately, I have seen cases where one feels as though they have been replaced by their partner's masturbation. Knowing that their partner can so easily pleasure his or herself, they may doubt their own skills in the bedroom. You mentioned in your question that you do not feel masturbation is a replacement for sex. Does your partner know this? Have you two discussed your ideal sex life? And do you feel that those ideals are being met in reality? If you are both feeling heard and satisfied in your partnered sex, then where does the real problem lie? If masturbation is something that you don't feel comfortable giving up, let your partner know that. Perhaps your partner would feel more comfortable knowing that you will masturbate only when they are truly unavailable (away at work, travelling, etc.). This way, masturbation is less likely to be perceived as a replacement for sex with your partner. Find out if your partner is interested in experimenting with phone or cyber sex when he or she is away to help further include them in your masturbatory activities.
