can I do a DIY trial separation myself in illinois

Hello, Anonymous. I'm not entirely sure what you mean by "trial" separation. In Illinois, you can file for a separation at the courthouse, and the marriage will still exist, but the court will essentially allow you to live apart. The court will not make a decision about division of property because, as the marriage still exists, there's no reason to separate it just yet. If you are separated without any court involvement, then your marriage will obviously still exist, but there may potentially be other consequences from the unofficial separation. For example, if your husband is away from the house for long enough, and if the house is marital property (which is likely, but I can't be sure from the information provided), then there is the chance that he could be considered to have abandoned the house and may forfeit some or all claim to it. Additionally, if the unofficial separation lasts long enough, it may create additional grounds for divorce due to abandonment. Regarding your husband's ability to come and go to and from the house,  it is likely that he can come and go from the house as he pleases, the same way you can right now. From the information you provided, it is likely that the house is marital property, which if it is, means that you both have equal rights and claims to the house, and technically, absent a court order, neither one of you may evict the other. His being out of the house is, as of now, not a legally binding agreement to not come and go. He still has as much ownership and rights over the house as you do. For a situation like this, it may be in your best interests to hire an attorney to get a legal separation for the two of you. Your marriage would still exist, so reconciliation is a possibility should you choose that option in the future. Likewise, should the separation not work, then divorce is always an option and may be pursued at a later date as well.