When me and my girlfriend are alone we have so much fun. But when she is out I am so insecure what she is doing. I have been divorced for 2 years and have 2 girls. My girls like her and she likes them, so it is not the kids. She is going through a divorce and her husband knows about us and is OK about it. She has no kids. I am losing her right now because I got jealous again it is not the first time I have been doing this to her. She does nothing wrong for me not to trust her.
My past I lost my dad about a year ago he was very sick and I knew this was the best for him to go with his wife. Lost my dads brother about 4 months ago. I have joint custody of my girls so this is good because they are the world to me, and now so is my girlfriend. Please let me know what I can do to stop the jealousy from happening.
Thank you

You can talk to your girlfriend for starter to explain all those feelings you have. I assume you don't want to lose her since you have lost many people in your life and that may explain your jealousy (aka your fear of losing her).
Then you can go and see a psychiatrist and work on yourself. If you are positive about changing, you'll be able to change.

First, recognize that there is a difference between jealousy and fear of losing someone.

Jealousy can be a symptom of the fear. Fear is the bigger issue.

You have lost two people to death, you lost your ex-wife to divorce, your children are only partly in your life, and there are probably several other relationship changes that have occurred of lesser impact but add up. You are afraid that she will be next so you are holding on too tightly. It is a common reaction to loss. Another common reaction is to push those close to you away before they can leave and hurt you. That you understand you are adversely affecting your relationship is a big first step.

Second, take time to work on your communication with her before you push her into leaving. Be honest about being afraid of losing her and that you need to work on your own insecurities. Remember that she needs self and friend time to be able to give you support emotionally and mentally.

Third, actually work on those insecurities and fears. Once you know where they are coming from it is a lot easier to see them for what they are. Accept that you can't always control people coming and going in your life and that there will be change. Find ways to give yourself some support in dealing with those changes other than relying solely on another person. For some people the gym, hobbies, clubs, sports, etc. give them some time away from the relationship to work on strengthening themselves.

One last thing, make sure that you aren't making her your only support. You need other friends, too.

It is good that you realize your problem and is looking for a solution. Besides having a girlfriend and kids do you have any friends? Instead of sitting around wondering what she is doing when she is out maybe you should hang out with some of your friends. If you keep doing what your doing your only going push her away. The both of you need to have a life outside of the relationship and you should look into some counselling as mention above.

Btw, sorry to hear about your father and uncle passing.

Sounds like many of your insecurity issues begin from within. You've been divorced before, so you will definitely have trust issues.

Furthermore, the woman that you are with is still married, yet she's with you. That factor will not help your already existing insecurity issues.

I'm sorry for your lose. However, I do feel that you should be focusing on your child and recovering from your loses, instead of contemplating a new relationship with a woman with so much baggage.

Try thinking before you speak, or act. If you don't you lose her.