At the age of 33, having sex for 8 to 10 times a week is quiet a good frequency. Desire to have a sex with other females can be considered normal sexual fantasy but that does not mean that you should go and have it. Somehow people who are in travelling job have this desire more frequently.
It is possible that simply by overdoing it, now you are sort of obsessed with it or may be bored with same partner/same positions. You may think of some novelties in your act so that you remain interested in your wife only. And if nothing works then only one mantra can work and that is ‘control’.