Can Catholics participate in non catholic weddings?

I am a baptized but unconfirmed Episcopal. I married a baptized and confirmed Methodist three years ago.( this was a first marriage for both of us & we share no immediate blood ties) Our wedding ceremony was not held in a church nor was there a mass (no communion), it was done by a Methodist reverend. I went to a catholic school for 12 years and have mostly Catholic friends. I had three Catholic bridesmaids all of which I was under the assumption got permission from their respective priest.
One of my bridesmaids (one of my closest friends for 20+years) is expressing concerns under pressure of her fundamental (does not wholly adhere to the Vatican II council reforms of the 60s) extremely conservative Catholic family that she should not have participated in our ceremony.

Ques: should she not have participated?
Ques: Could I have participated in her wedding in the Catholic Church?

My friend and her husband also did not attend the Protestant funeral of my Protestant father-in-law as he committed suicide after suffering extreme withdraw from switching prescription medication under a doctor's authorization as they said they could not attend a funeral of a suicide. 

Ques: according to doctrine are Catholics not allowed to attend services if suicide is the reason for the death?

I told my grieving husband that they could not come as they were out of town on business.

thank you for your time and knowledge,
gratefully Allison

The first link should be helpful for explaining under what circumstances we recommend attendance and participation in weddings. The second should give you peace about participating in your friend’s Protestant ceremony. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.
Recommended Reading:

[LIST]
*]What are the rules for attending weddings?
*]Can a Catholic be best man at a Protestant wedding?
[/LIST]
The following link links should assist you in better understanding the Catholic Church’s teaching on the salvation of those who commit suicide. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.
Recommended Reading:

[LIST]
]Is my grandmother in hell because she committed suicide?
]
Can culpability be completely mitigated in a suicide?**
]* How do I answer my children’s questions about suicide?**
[/LIST]

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