me = (yo a mi) yo quiero divertirme, te = (yo a ti) yo quiero divertirte, lo = (yo a él) la (yo a ella) le (yo a Usted) quiero divertirlo, quiero divertirla, quiero divertirle, nos = (yo a nosotros, aunque con este verbo no aplica), os = (yo a vosotros) quiero divertiros, los = (a ellos) las = (yo a ellas) les (yo a ustedes) quiero divertirlos, quiero divertirlas, quiero divertirles te = (tu a ti) quieres divertirte, me = (tu a mi) quieres divertirme, lo = (tú a el) la = (tú a ella) quieres divertirlo, quieres divertirla, nos = (tú a nosotros) quieres divertirnos, los = (tu a ellos) las = (tu a ellas) quieres divertirlos, quieres divertirlas. se = (él a él, ella a ella) quiere divertirse, me = (él a mí) quiere divertirme, te = (él a ti) quiere divertirte, la = (el o usted a ella) quiere divertirla, lo = (ella o usted a él) quiere divertirlo, le = (ella o el) quiere divertirlo nos = (nosotros a nosotros) queremos divertirnos, te = (nosotros a ti) queremos divertirte, lo = (nosotros a el) queremos divertirlo, la = (nosotros a ella) queremos divertirla, le = (nosotros a él) queremos divertirlo la (nosotros a ella) queremos divertirla, le (nosotros a usted) queremos divertirle, os = (nosotros a vosotros) queremos divertiros, los = (nosotros a ellos) queremos divertirlos, las (nosotros a ellas queremos divertilas, les = (nosotros a ustedes) queremos divertirles os = (vosotros a vosotros) vosotros queréis divertiros, queréis divertirme, queréis divertirlo, queréis divertirla, queréis divertirnos, queréis divertirlos, queréis divertirlas, queréis divertirles. se = ( ellos a ellos, ellas a ellas, ustedes a ustedes) quieren divertirse, quieren divertirme, quieren divertirte, quieren divertirlo, quieren divertirla, quieren divertirle, quieren divertirnos, quieren divertiros. Observa la conjugación corresponde a la persona y la partícula expresa a que persona se dirige la segunda acción.

Hi Nena The other answer are mentioning this is a reflexive verb, but not sure if you know what reflexive verb is. Not getting into details here, see this link to see what the reflx verb is but don't go any further on the page, just find out what a reflx verb is and come back to my answer: http://www.studyspanish.com/lessons/reflexive1.htm After you have learned that, we will jump on the part where it says, the reflexive pronouns are not subject pronouns; rather they are object pronouns. You are partly right if you want to use "divertirse" because that is a correct structure for a reflexive verb, if you were talking of himself, herself, itself. But you are talking of the subject "myself"... I want to amuse MYSELF. So here are the object pronouns for each subject you use: me (myself) te (yourself) se (himself, herself, yourself) nos (ourselves) os (yourselves) se (themselves, yourselves) That is why, it has to be "me" not "se", but it has nothing to do with the conjugation of the verb, it has to be with the object of the sentence, the object, as you should know, is the entity in the sentence that is acted upon by the subject, where the action falls. So your action falls on yourself, making it a reflexive verb, making it need to use "me" and not "se". I hope that makes sense.... :/

"Divertirse" is a reflexive verb; you can say: "Quiero divertir a mi sobrino", but if you want to amuse yourself, you must use the reflexive verb: Quiero divertirme.