Realize that unwarranted jealousy is your need to blame your feelings on someone else.
Analyze your feelings and put them in perspective of if they have justification or they are out of fear and insecurity. Try to look at objective realities, rather than presumptions or suppositions.
Realize that presumptions from jealousy can ruin a relationship.

I get what you're saying. We can project on to the other person what we don't want to admit is inside ourselves. It gets a bit tricky, that one.

The difficulty is knowing how to distinguish between justified jealousy or what is based on fear and insecurity. I find that the most difficult thing to do. Maybe when you have a tendency towards being jealous, it takes little provocation to get your mind wondering if there is justification, or not. I have been proven wrong so many times, that it's obvious to me by now that all the jealousy I've experienced in the past was based on pure conjecture.

There may have been moments when a partner was flirtatious and genuinely liked another woman. I have to remind myself that it isn't a threat if that happens and it doesn't mean I'm going to lose my partner, simply because he has already reassured me I have nothing to worry about.

Sometimes you just need to make the decision to trust someone, I'm told.

The biggest motivation for change is knowing I want my relationship to be as happy as it can, and that won't be possible if I ruin the relationship with jealousy.

Basically to distinguish you need to learn to set aside the emotional voices in your head so you can learn to listen to your gut instincts.
Start writing down your fears vs the actual 'proof'
Write what you feel he is doing that makes you feel this way along with actual red flags. Then leave a space to write down any confirmations that prove your feelings were unsubstantiated.
For example:
I spent two hours worrying that he may have been out with some other woman. The red flags were that he was two hours late coming home from work. Then when you find out concrete evidence write it down such as neighbor says he saw him that night helping a broken down vehicle on the side of the road.
Title it something like therapy book to overcome MY insecurities in case he runs across it and takes it the wrong way or else possibly discuss it with him if he already knows you have a problem. But then if he IS guilty he could fake proof.

Thanks for helping me through a prickly patch of 'jealousy' :)

We're back on track at the moment, having had a quiet and relaxed weekend. Given the support here, I managed not to let my jealousy get out of control this time.

Unless he tells me differently or there is solid evidence he is with another woman, which I know he hasn't been... as he took measures to reassure me last week that nothing was going on other than delivering a fridge (went with his daughter and was there only 20minutes), and that I should have nothing to worry about, I'll get back to trusting our relationship. There are things we're planning to do together over the next few months and our kids are all happy at the moment, so why not enjoy what we have.

My daughter starts high school tomorrow, by the way. It's all very exciting.

My partner swept me off my feet again today with surprise airline tickets for he and I and my daughter to holiday in New Zealand this April. It's the most wonderful 'act of love' anyone has ever done for me... and I can't believe how lucky I've been to have fallen in love with someone as special as him. I think you guys may have helped make that possible by helping me work through something that could have easily turned out differently without your support :)

YESSSSSSSS!! :D

That is WONDERFUL!!

I hope you have a GREAT time!! My mother spent her teen years in New Zealand, always wanted to go and meet the relatives. If you see any big hairy apes, say hello for me OK? Lol

Really good news to hear that.

Three cheers to a very generous and thoughtful partner!