Thank-you everyone for all the responses. Yes the whole scent thing dawned on me but because I really dislike that smell they get when at the vets they both got baths shortly after getting home that afternoon. Its been almost a mth & a half since the D day. And her attitude is getting worse, she growls if he gets within 10 ft of her.So far thats all that has happened as he doesn't insist on trying to get any closer. Its just sad, as he really doesn't understand.
I am a huge believer in fixing my pets, the only reason this one hadn't gotton fixed we were unsure of her age and she didn't show any signs of being in heat-then all of a sudden her lil belly was huge.
I have had enough cats all my life so I know first hand their attitudes do change...sometimes daily..lol
I will just wait and see what happens-again a huge thanks!!!!

It took my female over 6 months after her and baby boy were fixed to be even near the young male again. Then they became mousing pals, run thru the house together, share window sills, etc. Give them time and keep giving each their attention!

Have you considered taking her back to the vet to make sure she is doing well. My niece had her cat spayed and she seemed to be fine for a few weeks, and then unexpectedly passed on from an infection that they weren't even aware of she had. her personality had changed somewhat but everyone thought it was from her surgery healing. I do hope that they become friends again. I have 7 cats and not all of them were overly friendly after their surgeries. I would have her checked at the vet.

As many have responded, this is not unusual. But I can recommend something to help with her behavior towards him (and others). Look into Pheremones for cats. Products like Feliway and others are pricey BUT you don't have to see a vet for a RX or try to shove pills down their throat, so I think of them as VERY AFFORDABLE. These pheremones are synthetically made to mimic those that cats rub on you when they push their cheeks/face on you (or their surroundings). It helps the cats feel safe, wanted, and friendly. My understanding is that they now come in colars, sprays, and diffusers. PM me for more details.

Oh this sounds interesting I hadn't heard of a product like what you wrote about. Great suggestions everyone, thanks.

well i have 3 cats. ,mamma and two kittens, girls. mamma got pregnant again before we got her completely inside and she ignored her two girls due to that. the girls became best buds and were "joined at the hip" for awhile. then mamma had six more kittens. after they were weaned and she lost interest, the girls "unjoined" themselves. i found homes for 3 of the second litter and gave 3 to a place that found homes for them.
now mamma and her two girls chase each other, wash each other, hiss at each other, slap at each other, etc.
they are just 3 cats living in the same house. not mamma and dtrs.
you two are just 2 cats living in the same house. scold your mamma or son when either one is mean to the other. they should learn by the tone of your voice what is excepted or not.
good luck.