Cultural and life experience differences of all kinds can affect our romantic relationships and even our friendships, so the question is one worth thinking about. Clearly you do have some significant differences in your backgrounds and life experiences. This neither dooms your relationship nor assures its success. Given that you have been together for almost two years, you have probably already come to terms with many of these background differences. This can pave the road to successful resolution of other issues that may arise as you move into a more committed relationship.
The answer to your question depends a lot on how flexible each of you are and whether you can step into each other’s shoes when questions of cultural difference arise. For example, if she understands the importance of your family relationships and has been open to forming relationships with your children, grandchildren, and other members of your extended family, the fact that she has no children of her own should pose no problem. In fact, couples that marry at older ages can have conflicts about whose family members they spend time with and how much time they are going to spend with each other’s families. If your fiancé doesn’t have children, this actually reduces the potential for conflict in this arena.
Similarly, many long-time married people are now single due to divorce or death of a spouse. Frequently, they have had more than one relationship prior to meeting a new person they want to marry. While it may not be your cultural etiquette to have friendships with ex-dating partners, this need not be a problem for the two of you as long as you feel secure that her past relationships are truly friendships with no lingering romantic feelings.
If you are not a particularly jealous person, these friendships can be positive for your relationship with your fiancé. Such friends can offer a unique window of insight into her character and past experiences. In addition, the fact that she has been able to end other romantic relationships and transition to friendship with those partners also says something quite positive about her. The ability to do this is actually pretty rare.
Your different life experiences are less important than whether you have compatible interests, shared values, and a common vision for your future. These differences in life experience keep the relationship fresh and interesting and can even enrich your relationship in unexpected ways.