No, you can't fly back with bear spray. However, you can mail it back ground (parcel post).
Get a big can, if possible one with a harness holding it in the middle of your chest. It's recommended you replace bear spray every year. While the pepper doesn't go bad, the plastic button and funnel can malfunction with age. It's a good excuse to practice with the old one.
There's safety in numbers. Groups of 3+ virtually guarantee no encounters (however I'm usually with only my beloved).
Don't worry about sex in the backcountry. Bear expert Doug Peacock (he was the basis for Hayduke in "The Monkey Wrench Gang") flatly states bears have zero interest in human sexual odors. Personal experience agrees with this.
And in the end,
the love you take,
is equal to the love,