The surgery you underwent was for a prolapse of the uterus maybe not for the vagina. The vagina has muscles all around it in the so called pelvic floor. The so called vaginal tightening surgeries are in fact not required at all as the vagina can accommodate to any size.
As far as intercourse is concerned this should not cause any problem. As you have just undergone a surgery please give it 6 - 8 weeks to settle down you will see that you have no hindrance to your normal sexual activities. You can also consult your gynaecologist again regarding the same and she might be able to advise you regarding some pelvic floor exercises which will help you in tightening your vagina during intercourse. There is no need to get depressed due to this.