La soledad

La vida es una bonita cosa (algo bonito)
Lleno de gente y sus (perfectly fine, but you could omit it too= risas.
Honestamente, me encanta su presencia.

Pero, nunca tenía amigos.
Miraba como los niños corrían,
y como los amantes se sentaban a mi lado.
Pero nunca les podría tocar,
ni podría comunicarme con ellos/ ni me podría comunicar con ellos.
Así, me quedaba en silencio.
Y aunque nos parecíamos juntos,
no lo eramos… nunca eramos amigos.

Sigue vivo la (Sigo viviendo en) soledad…

A menudo, los coquetos (ligones?) me mostraban a sus mujeres;
- como (not necessary, and it would be with accent in the first "o") me encanta la sonrisa en sus caras.
No obstante, tengo que aceptar la realidad de que nunca seremos más de
extrañjeros (que extraños)

algo bonito

First, the order of the words wasn't correct. It sounds more natural in this case to put the adjective at the end of the sentence. Also "cosa" (thing) is normally more for material things. You have to understand "vida" (life) as something more difficult to define, so we normally use instead of "cosa" "algo" (something)

me

You need in that sentence to use "me". It can be written in both the places I pointed out. The thing is, in English you would say something like "nor could I communicate with them" (something like that, I'm not that good at English, sorry), but in Spanish we don't need to use the subject of the sentence always, we can just use a pronoum to point how is the person that recieves the action, in this case yourself.

juntos

I think that you written "juntos" because you wanted to imply that you and the other children seem to be similar each other. Well, in Spanish you don't to write that, and in fact, sounds odd in this sentence. The "nos" of "nos parecíamos" is a pronoum, and in this case it's acting as a reciprocal pronoum. This means that the pronoum itself implies that the action is reciprocal between at least two people.

Sigo viviendo en

I understood that you meant that you are still living in loneliness...if you wanted to say that loneliness is still alive it would be "Sigue viva la soledad".

coquetos

When we say someone is "coqueto" we are saying something like the like to look good, using fancy clothes or make-up, for example. If you want to say something like the people that flirt a lot, it would be possible tu use in that sentence "ligones".

extraños

"extranjero" is someone from a different country than yours...I think you use in English foreign both for people from other country and for people that is different from you, or that you dont know. Well, in Spanish we make a difference between the people that is "extraña" (we don't know or understand) and the people from other places or "extranjero".

You have written something really deep, sounds nearly like a modern poem! I really liked correcting it. The mistakes aren't serious, you are good at Spanish. Keep practising like this! Also, sorry if my correction was too long and boring, didn't want to bother you.

La soledad

La vida es una bonita cosa
Llena de gente y sus risas.
Honestamente, me encanta su presencia.

Pero, nunca tenía amigos.
Miraba como los niños corrían,
y como los amantes se sentaban a mi lado.
Pero nunca les podría tocar,
ni podría comunicarme con ellos.
Así, me quedaba en silencio.
Y aunque nos parecíamos juntos,
no lo estábamos… nunca éramos amigos.

Sigue viva la soledad…

A menudo, los coquetos me mostraban a sus mujeres;
- cómo me encanta la sonrisa en sus caras.
No obstante, tengo que aceptar la realidad de que nunca seremos más que
extranjeros.

Me ha encantado tu poesía.

No estés triste.

Pues como se dice en una gran película.

"La vida es un estado de la mente"

Un cariñoso saludo.

G.