Divorce and Weddings
Second marriages carry a lot of cargo, and it's no good sweeping your past under the carpet. Previous marriages should be explicitly acknowledged (without recrimination), and then children, friends, and even the odd ex-in-law will not feel hurt and rejected.
It is understandable that the bride and groom will want children from previous relationships to be involved in the celebration of their new marriage. Children are often happy to play a special role, such a being a bridesmaid, pageboy, or even best man, but they should always be consulted in case they wish to stay in the background.
The couple must discuss these issues at an early stage, both with the children and with ex-partners. Pressurising children into situations they find uncomfortable might create resentment and uneasiness.
Marrying a First-Timer
If you are divorced and are contemplating a union with a partner who is getting married for the first time, you may well find an air of nervousness and awkwardness permeating your relations with your new in-laws. This is understandable - in their eyes you do not have a good track record; you have left one marriage behind and might do the same again. Accept their reservations without resentment, and focus all your energy on reassuring them, and reiterating your commitment to the new marriage. Don't feel hurt or offended by their hesitation - it's only natural.
Don't allow yourself to become jaded by your first marriage. Always remember that your new partner is embarking on a fresh adventure, and don't be dismissive of their desire to enjoy the traditional trappings of marriage - even if all the paraphernalia of marriage reminds you uncomfortably of your first, failed, attempt, you must put these feelings behind you.
Attending an Ex-Partner's Wedding
Traditionally, ex-partners weren't invited to remarriages, but social conventions have become more fluid, and - especially if you have managed to establish a reasonably civilised relationship with your ex - you may find yourself confronted with an invitation. Think carefully about whether you should attend. Examine your own feelings with forensic care, and only accept if you are absolutely sure that you can handle it. You are not under an obligation to attend, even if children are involved, and are quite within your rights to decline gracefully (no apologies or explanations needed).
If you do attend, however, make sure that your behaviour is impeccable. Congratulate your ex and the new partner warmly and armour yourself throughout the day with faultless good manners. Whatever you do, don't drink too much and turn maudlin or aggressive - you might be wise to tip off a friend to look out for you, and make it their job to escort you home as soon as they see your social façade begin to wobble.
If you are divorced and planning the wedding of your daughter, you will need to bear in mind that this is - first and foremost - her day. It is perfectly natural for your daughter to want both her parents (and new partners/spouses, if necessary) to attend the wedding, and if that is what she wants, then you really must try and accommodate her wishes. Inflicting the detritus of your own failed marriage on your daughter's hopes and aspirations for married bliss is very cruel.
So bite back your bitterness, and do not hint to your daughter that you would find certain guests impossibly difficult to welcome. Take your lead from her, and do your utmost to behave in a civilised manner on the day.
Even if you are not hosting the wedding (eg if your son is marrying, or if your son or daughter are organising the wedding for themselves), the same rules apply. Unless you are estranged, you must assume that they want both you, and your ex partner, to attend, and - whatever the circumstances - you should accede to their wishes with the minimum of fuss.